> For the complete documentation index, see [llms.txt](https://dev.solid-run.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dev.solid-run.com/nxp/imx8/sbc-platform/imx8m-other-articles/hummingboard-pulse-ripple-b2b-pin-mapping.md).

# HummingBoard Pulse/Ripple B2B Pin Mapping

## Background

Below tables reference the HummingBoard Pulse rev 2.4 pin mapping description for all the i.MX8M SOM variants (i.MX8M,i.MX8M Mini,i.MX8M Plus). All the SOMs share a similar pinout, thus allowing them to be used on the same development platform.

## J5001 connector

| **PIN** | **HummingBoard Pulse 2.4** | **IMX8M rev 2.0**                                        | **IMX8M Mini rev 1.2**                                   | **IMX8M Plus rev 1.0**                              |   | **PIN** | **HummingBoard Pulse 2.4** | **IMX8M rev 2.0**                               | **IMX8M Mini rev 1.2**                          | **IMX8M Plus rev 1.0**                                    |
| ------- | -------------------------- | -------------------------------------------------------- | -------------------------------------------------------- | --------------------------------------------------- | - | ------- | -------------------------- | ----------------------------------------------- | ----------------------------------------------- | --------------------------------------------------------- |
| 1       | TP4                        | PMIC\_ON                                                 | NC                                                       | NC                                                  |   | 2       | NC                         | NC                                              | DSI\_EN, [GPIO1.IO](http://GPIO1.IO)\[08]       | DSI\_EN, [GPIO1.IO](http://GPIO1.IO)\[08]                 |
| 3       | DIP-SWITCH                 | BOOT\_MODE0                                              | BOOT\_MODE0                                              | BOOT\_MODE0                                         |   | 4       | DSI-CON (J19) or DSI-HDMI  | DSI\_DN3                                        | DSI\_DN3                                        | DSI\_DN3                                                  |
| 5       | DIP-SWITCH                 | BOOT\_MODE1                                              | BOOT\_MODE1                                              | BOOT\_MODE1                                         |   | 6       | DSI-CON (J19) or DSI-HDMI  | DSI\_DP3                                        | DSI\_DP3                                        | DSI\_DP3                                                  |
| 7       | GND                        | GND                                                      | GND                                                      | GND                                                 |   | 8       | GND                        | GND                                             | DSI\_TS\_Nint, [GPIO1.IO](http://GPIO1.IO)\[09] | GND                                                       |
| 9       | DSI-CON (J19) or DSI-HDMI  | DSI\_CKP                                                 | DSI\_CKP                                                 | DSI\_CKP                                            |   | 10      | GND                        | GND                                             | GND                                             | GND                                                       |
| 11      | DSI-CON (J19) or DSI-HDMI  | DSI\_CKN                                                 | DSI\_CKN                                                 | DSI\_CKN                                            |   | 12      | DSI-CON (J19) or DSI-HDMI  | DSI\_DN0                                        | DSI\_DN0                                        | DSI\_DN0                                                  |
| 13      | GND                        | GND                                                      | GND                                                      | GND                                                 |   | 14      | DSI-CON (J19) or DSI-HDMI  | DSI\_DP0                                        | DSI\_DP0                                        | DSI\_DP0                                                  |
| 15      | DSI-CON (J19) or DSI-HDMI  | DSI\_DN2                                                 | DSI\_DN2                                                 | DSI\_DN2                                            |   | 16      | GND                        | GND                                             | GND                                             | GND                                                       |
| 17      | DSI-CON (J19) or DSI-HDMI  | DSI\_DP2                                                 | DSI\_DP2                                                 | DSI\_DP2                                            |   | 18      | Mini-PCIe (J20, optional)  | PCIE1\_REF\_CLKP\_CN                            | NC                                              | LVDS0\_CLK\_P                                             |
| 19      | GND                        | GND                                                      | GND                                                      | GND                                                 |   | 20      | Mini-PCIe (J20, optional)  | PCIE1\_REF\_CLKN\_CN                            | NC                                              | LVDS0\_CLK\_N                                             |
| 21      | DSI-CON (J19) or DSI-HDMI  | DSI\_DN1                                                 | DSI\_DN1                                                 | DSI\_DN1                                            |   | 22      | GND                        | GND                                             | GND                                             | GND                                                       |
| 23      | DSI-CON (J19) or DSI-HDMI  | DSI\_DP1                                                 | DSI\_DP1                                                 | DSI\_DP1                                            |   | 24      | M.2\_W\_DIS#               | PCIE\_nPME, [GPIO3.IO](http://GPIO3.IO)\[5      | PCIE\_CLKREQ, [GPIO1.IO](http://GPIO1.IO)\[12]  | M.2\_W\_DIS#, [GPIO1.IO](http://GPIO1.IO)\[13]            |
| 25      | GND                        | GND                                                      | GND                                                      | GND                                                 |   | 26      | Mini-PCIe\_W\_DIS#         | PCIe\_nWAKE, [GPIO3.IO](http://GPIO3.IO)\[12]   | PCIe\_Nwake, [GPIO2.IO](http://GPIO2.IO)\[20]   | Mini-PCIe\_W\_DIS#, [GPIO1.IO](http://GPIO1.IO)\[05]      |
| 27      | M.2\_WAKW\_ON\_LAN (PCIe)  | PWM1\_OUT, [GPIO1.IO](http://GPIO1.IO)\[1]               | DSI\_BL\_PWM,[GPIO1.IO](http://GPIO1.IO)\[01]            | M.2\_WAKW\_ON\_LAN,[GPIO1.IO](http://GPIO1.IO)\[12] |   | 28      | USB1\_PWR\_EN              | USB1\_SS\_SEL, [GPIO3.IO](http://GPIO3.IO)\[15] | PCIe\_nRST, [GPIO4.IO](http://GPIO4.IO)\[21]    | USB1\_PWR\_EN, [GPIO1.IO](http://GPIO1.IO)\[15]           |
| 29      | MIKROBUS (J10-4)           | UART3\_TXD, [GPIO5.IO](http://GPIO5.IO)\[27]             | UART1\_TXD, [GPIO5.IO](http://GPIO5.IO)\[23]             | UART3\_TXD, [GPIO5.IO](http://GPIO5.IO)\[7]         |   | 30      | GND                        | GND                                             | GND                                             | GND                                                       |
| 31      | MIKROBUS (J10-3)           | UART3\_RXD, [GPIO5.IO](http://GPIO5.IO)\[26]             | UART1\_RXD, [GPIO5.IO](http://GPIO5.IO)\[22]             | UART3\_RXD, [GPIO5.IO](http://GPIO5.IO)\[6]         |   | 32      | Mini-PCIe (J20, optional)  | PCIE1\_TXP\_C                                   | NC                                              | LVDS0\_TX2\_N                                             |
| 33      | GND                        | GND                                                      | GND                                                      | GND                                                 |   | 34      | Mini-PCIe (J20, optional)  | PCIE1\_TXN\_C                                   | NC                                              | LVDS0\_TX2\_P                                             |
| 35      | NC                         | NC                                                       | PCIe\_nDIS, [GPIO1.IO](http://GPIO1.IO)\[05]             | NC                                                  |   | 36      | GND                        | GND                                             | GND                                             | GND                                                       |
| 37      | MIKROBUS (J10-1)           | UART3\_CTS, [GPIO5.IO](http://GPIO5.IO)\[8]              | UART1\_CTS, [GPIO5.IO](http://GPIO5.IO)\[26]             | UART3\_CTS, [GPIO5.IO](http://GPIO5.IO)\[8]         |   | 38      | Mini-PCIe (J20, optional)  | PCIE1\_RXP\_C                                   | NC                                              | LVDS0\_TX3\_N                                             |
| 39      | MIKROBUS (J10-2)           | UART3\_RTS, [GPIO5.IO](http://GPIO5.IO)\[9]              | UART1\_RTS, [GPIO5.IO](http://GPIO5.IO)\[27]             | UART3\_RTS, [GPIO5.IO](http://GPIO5.IO)\[9]         |   | 40      | Mini-PCIe (J20, optional)  | PCIE1\_RXN\_C                                   | NC                                              | LVDS0\_TX3\_P                                             |
| 41      | HEADER, DIP-SW             | SAI1\_TXD2, [GPIO4.IO](http://GPIO4.IO)\[14] (BT\_CFG10) | SAI1\_TXD2, [GPIO4.IO](http://GPIO4.IO)\[14] (BT\_CFG10) | SAI2\_TXC, [GPIO4.IO](http://GPIO4.IO)\[25]         |   | 42      | GND                        | GND                                             | GND                                             | GND                                                       |
| 43      | DSI\_TS\_nINT (DSI-HDMI)   | DSI\_TS\_nINT, [GPIO5.IO](http://GPIO5.IO)\[7]           | CSI\_PWDN, [GPIO1.IO](http://GPIO1.IO)\[07]              | SAI2\_MCLK, [GPIO4.IO](http://GPIO4.IO)\[27]        |   | 44      | LED (D34)                  | UART2\_RXD, [GPIO5.IO](http://GPIO5.IO)\[24]    | UART3\_RXD, [GPIO5.IO](http://GPIO5.IO)\[6]     | SAI2\_RXC, [GPIO4.IO](http://GPIO4.IO)\[22] (UART1\_RX)   |
| 45      | NC                         | NC                                                       | MIPI\_CSI0\_MCLK\_OUT, [GPIO1.IO](http://GPIO1.IO)\[14]  | SAI2\_TXD, [GPIO4.IO](http://GPIO4.IO)\[26]         |   | 46      | LED (D33)                  | UART2\_TXD, [GPIO5.IO](http://GPIO5.IO)\[25]    | UART3\_TXD, [GPIO5.IO](http://GPIO5.IO)\[7]     | SAI2\_RXFS, [GPIO4.IO](http://GPIO4.IO)\[21] (UART1\_TX)  |
| 47      | GND                        | GND                                                      | GND                                                      | GND                                                 |   | 48      | LED (D32)                  | UART2\_CTS, [GPIO5.IO](http://GPIO5.IO)\[28]    | UART3\_CTS, [GPIO5.IO](http://GPIO5.IO)\[8]     | SAI2\_RXD, [GPIO4.IO](http://GPIO4.IO)\[23] (UART1\_CTS)  |
| 49      | NC                         | NC                                                       | MIPI\_CSI0\_RST#, [GPIO1.IO](http://GPIO1.IO)\[06]       | LVDS0\_TX1\_N                                       |   | 50      | LED (D31)                  | UART2\_RTS, [GPIO5.IO](http://GPIO5.IO)\[29]    | UART3\_RTS, [GPIO5.IO](http://GPIO5.IO)\[9]     | SAI2\_TXFS, [GPIO4.IO](http://GPIO4.IO)\[24] (UART1\_RTS) |
| 51      | HEADER, DIP-SW             | SAI1\_TXD4, [GPIO4.IO](http://GPIO4.IO)\[16] (BT\_CFG12) | SAI1\_TXD4, [GPIO4.IO](http://GPIO4.IO)\[16] (BT\_CFG12) | LVDS0\_TX1\_P                                       |   | 52      | GND                        | GND                                             | GND                                             | GND                                                       |
| 53      | WIFI\_DP (HUB to IMX8M)    | WIFI\_USB\_DP                                            | I2C4\_SCL                                                | LVDS0\_TX0\_N                                       |   | 54      | CSI-CON(CON7)              | CSI\_P1\_DN0                                    | CSI\_DN0                                        | CSI\_DN0                                                  |
| 55      | WIFI\_DN (HUB to IMX8M)    | WIFI\_USB\_DN                                            | I2C4\_SDA                                                | LVDS0\_TX0\_P                                       |   | 56      | CSI-CON(CON7)              | CSI\_P1\_DP0                                    | CSI\_DP0                                        | CSI\_DP0                                                  |
| 57      | GND                        | GND                                                      | GND                                                      | GND                                                 |   | 58      | GND                        | GND                                             | GND                                             | GND                                                       |
| 59      | CSI-CON(CON7)              | CSI\_P1\_CKP                                             | CSI\_CKP                                                 | CSI\_CKP                                            |   | 60      | CSI-CON(CON7)              | CSI\_P1\_DP2                                    | CSI\_DP2                                        | CSI\_DP2                                                  |
| 61      | CSI-CON(CON7)              | CSI\_P1\_CKN                                             | CSI\_CKN                                                 | CSI\_CKN                                            |   | 62      | CSI-CON(CON7)              | CSI\_P1\_DN2                                    | CSI\_DN2                                        | CSI\_DN2                                                  |
| 63      | GND                        | GND                                                      | GND                                                      | GND                                                 |   | 64      | GND                        | GND                                             | GND                                             | GND                                                       |
| 65      | CSI-CON(CON7)              | CSI\_P1\_DP3                                             | CSI\_DP3                                                 | CSI\_DP3                                            |   | 66      | CSI-CON(CON7)              | CSI\_P1\_DP1                                    | CSI\_DP1                                        | CSI\_DP1                                                  |
| 67      | CSI-CON(CON7)              | CSI\_P1\_DN3                                             | CSI\_DP3                                                 | CSI\_DP3                                            |   | 68      | CSI-CON(CON7)              | CSI\_P1\_DN1                                    | CSI\_DN1                                        | CSI\_DN1                                                  |
| 69      | GND                        | GND                                                      | GND                                                      | GND                                                 |   | 70      | GND                        | GND                                             | GND                                             | GND                                                       |

## J7 connector

| **PIN** | **HummingBoard Pulse 2.4** | **IMX8M rev 2.0**                                      | **IMX8M Mini rev 1.2**                                 | **IMX8M Plus rev 1.0**                        |   | **PIN** | **HummingBoard Pulse 2.4** | **IMX8M rev 2.0**                                        | **IMX8M Mini rev 1.2**                                   | **IMX8M Plus rev 1.0**                                  |
| ------- | -------------------------- | ------------------------------------------------------ | ------------------------------------------------------ | --------------------------------------------- | - | ------- | -------------------------- | -------------------------------------------------------- | -------------------------------------------------------- | ------------------------------------------------------- |
| 1       | ETH\_NIC (Intel, U6)       | PCIE2\_REF\_CLKP\_CN                                   | PCIEC\_CLKN (Optional)                                 | PCIEC\_CLKN                                   |   | 2       | ETH\_NIC (Intel, U6)       | PCIE2\_RXN                                               | PCIEC\_RXN (Optional)                                    | PCIE\_RXN                                               |
| 3       | ETH\_NIC (Intel, U6)       | PCIE2\_REF\_CLKN\_CN                                   | PCIEC\_CLKP (Optional)                                 | PCIEC\_CLKP                                   |   | 4       | ETH\_NIC (Intel, U6)       | PCIE2\_RXP                                               | PCIEC\_RXP (Optional)                                    | PCIE\_RXP                                               |
| 5       | GND                        | GND                                                    | GND                                                    | GND                                           |   | 6       | GND                        | GND                                                      | GND                                                      | GND                                                     |
| 7       | ETH\_NIC (Intel, U6)       | PCIE2\_TXN                                             | PCIEC\_TXN (Optional)                                  | PCIEC\_TXN                                    |   | 8       | HEADER (CON4)              | SAI3\_MCLK, [GPIO5.IO](http://GPIO5.IO)\[2]              | SAI3\_MCLK, [GPIO5.IO](http://GPIO5.IO)\[2]              | NC                                                      |
| 9       | ETH\_NIC (Intel, U6)       | PCIE2\_TXP                                             | PCIEC\_TXP (Optional)                                  | PCIEC\_TXP                                    |   | 10      | HEADER (CON4)              | SAI3\_RXC, [GPIO4.IO](http://GPIO4.IO)\[29]              | SAI3\_RXC, [GPIO4.IO](http://GPIO4.IO)\[29]              | Mini-PCIe\_PREST#, [GPIO1.IO](http://GPIO1.IO)\[01]     |
| 11      | GND                        | GND                                                    | GND                                                    | GND                                           |   | 12      | HEADER (CON4)              | SAI1\_TXC, [GPIO4.IO](http://GPIO4.IO)\[11]              | SAI1\_TXC, [GPIO4.IO](http://GPIO4.IO)\[11]              | SPDIF\_RX, [GPIO5.IO](http://GPIO5.IO)\[4]              |
| 13      | M.2\_RESET#                | SAI3\_TXFS, [GPIO4.IO](http://GPIO4.IO)\[31]           | SAI3\_TXFS, [GPIO4.IO](http://GPIO4.IO)\[31]           | M.2\_RESET#, [GPIO1.IO](http://GPIO1.IO)\[06] |   | 14      | POE\_AT\_DET               | SAI3\_TXC [GPIO5.IO](http://GPIO5.IO)\[0]                | SAI3\_TXC, [GPIO5.IO](http://GPIO5.IO)\[0]               | POE\_AT\_DET, [GPIO1.IO](http://GPIO1.IO)\[09]          |
| 15      | RTC\_CLKO (RTC Int.)       | SAI3\_RXFS, [GPIO4.IO](http://GPIO4.IO)\[28]           | SAI3\_RXFS, [GPIO4.IO](http://GPIO4.IO)\[28]           | NC                                            |   | 16      | DSI-CON (J19) or DSI-HDMI  | SPDIF\_TX, [GPIO5.IO](http://GPIO5.IO)\[3]               | SPDIF\_TX, [GPIO5.IO](http://GPIO5.IO)\[3]               | SPDIF\_TX, [GPIO5.IO](http://GPIO5.IO)\[3]              |
| 17      | GND                        | GND                                                    | GND                                                    | GND                                           |   | 18      | M.2\_PCIe\_3V3\_EN         | IR\_CAP, [GPIO1.IO](http://GPIO1.IO)\[12]                | IR\_CAP, [GPIO1.IO](http://GPIO1.IO)\[13]                | M.2\_PCIe\_3V3\_EN, [GPIO1.IO](http://GPIO1.IO)\[10]    |
| 19      | HDMI CON (J1)              | HDMI\_TXP2                                             | NC                                                     | HDMI\_TXP2                                    |   | 20      | HEADER (CON4)              | SAI1\_TXD7, [GPIO4.IO](http://GPIO4.IO)\[19] (BT\_CFG15) | SAI1\_TXD7, [GPIO4.IO](http://GPIO4.IO)\[19] (BT\_CFG15) | SPDIF\_EXT\_CLK, [GPIO5.IO](http://GPIO5.IO)\[5]        |
| 21      | HDMI CON (J1)              | HDMI\_TXN2                                             | CLKOUT1                                                | HDMI\_TXN2                                    |   | 22      | HEADER (CON4)              | SAI1\_TXD0, [GPIO4.IO](http://GPIO4.IO)\[12] (BT\_CFG8)  | SAI1\_TXD0, [GPIO4.IO](http://GPIO4.IO)\[12] (BT\_CFG8)  | NC                                                      |
| 23      | GND                        | GND                                                    | CLKOUT2                                                | GND                                           |   | 24      | HEADER (CON4)              | SAI1\_TXD1, [GPIO4.IO](http://GPIO4.IO)\[13] (BT\_CFG9)  | SAI1\_TXD1, [GPIO4.IO](http://GPIO4.IO)\[13] (BT\_CFG9)  | DSI\_EN, [GPIO1.IO](http://GPIO1.IO)\[08]               |
| 25      | HDMI CON (J1)              | HDMI\_TXP1                                             | NC                                                     | HDMI\_TXP1                                    |   | 26      | USB-HUB\_RST#              | SAI3\_RXD, [GPIO4.IO](http://GPIO4.IO)\[30]              | SAI3\_RXD, [GPIO4.IO](http://GPIO4.IO)\[30]              | USB-HUB\_RST#, [GPIO1.IO](http://GPIO1.IO)\[15]         |
| 27      | HDMI CON (J1)              | HDMI\_TXN1                                             | NC                                                     | HDMI\_TXN1                                    |   | 28      | HEADER (CON4)              | SAI1\_TXD3, [GPIO4.IO](http://GPIO4.IO)\[15] (BT\_CFG11) | SAI1\_TXD6, [GPIO4.IO](http://GPIO4.IO)\[18] (BT\_CFG14) | QSPIA\_DATA0, [GPIO3.IO](http://GPIO3.IO)\[6]           |
| 29      | GND                        | GND                                                    | NC                                                     | GND                                           |   | 30      | HEADER (CON4)              | SAI1\_TXFS, [GPIO4.IO](http://GPIO4.IO)\[10]             | SAI1\_TXFS, [GPIO4.IO](http://GPIO4.IO)\[10]             | QSPIA\_DATA1, [GPIO3.IO](http://GPIO3.IO)\[7]           |
| 31      | HDMI CON (J1)              | HDMI\_TXP0                                             | NC                                                     | HDMI\_TXP0                                    |   | 32      | TP6                        | nWDOG, [GPIO1.IO](http://GPIO1.IO)\[2]                   | SAI3\_RXC, [GPIO4.IO](http://GPIO4.IO)\[29]              | QSPIA\_DATA2, [GPIO3.IO](http://GPIO3.IO)\[8]           |
| 33      | HDMI CON (J1)              | HDMI\_TXN0                                             | NC                                                     | HDMI\_TXN0                                    |   | 34      | NC                         | NC                                                       | SYS\_STATUS, [GPIO3.IO](http://GPIO3.IO)\[16]            | QSPIA\_DATA3, [GPIO3.IO](http://GPIO3.IO)\[9]           |
| 35      | GND                        | GND                                                    | NC                                                     | GND                                           |   | 36      | HEADER (CON4)              | SAI1\_MCLK, [GPIO4.IO](http://GPIO4.IO)\[20]             | SAI1\_MCLK, [GPIO4.IO](http://GPIO4.IO)\[20]             | QSPIA\_Nss0, [GPIO3.IO](http://GPIO3.IO)\[1]            |
| 37      | HDMI CON (J1)              | HDMI\_CLKP                                             | NC                                                     | HDMI\_CLKP                                    |   | 38      | CSI-CON(CON7)              | CLKO2, [GPIO1.IO](http://GPIO1.IO)\[15]                  | UART2\_CTS, [GPIO5.IO](http://GPIO5.IO)\[28]             | UART4\_TXD, [GPIO5.IO](http://GPIO5.IO)\[29]            |
| 39      | HDMI CON (J1)              | HDMI\_CLKN                                             | CLKIN1                                                 | HDMI\_CLKN                                    |   | 40      | NC                         | NC                                                       | NC                                                       | QSPIA\_SCLK, [GPIO3.IO](http://GPIO3.IO)\[0]            |
| 41      | GND                        | GND                                                    | GND                                                    | GND                                           |   | 42      | GND                        | GND                                                      | GND                                                      | GND                                                     |
| 43      | HDMI CON (J1)              | HDMI\_CEC                                              | CLKIN2                                                 | HDMI\_CEC                                     |   | 44      | LED (D30)                  | [GPIO5.IO](http://GPIO5.IO)\[21]                         | UART2\_RTS, [GPIO5.IO](http://GPIO5.IO)\[29]             | UART4\_RXD, [GPIO5.IO](http://GPIO5.IO)\[28]            |
| 45      | HDMI CON (J1)              | HDMI\_DDC\_SCL                                         | NC                                                     | HDMI\_DDC\_SCL                                |   | 46      | HEADER (CON4)              | SAI1\_RXD7, [GPIO4.IO](http://GPIO4.IO)\[9] (BT\_CFG7)   | SAI1\_RXD7, [GPIO4.IO](http://GPIO4.IO)\[9] (BT\_CFG7)   | MB-RST, [GPIO1.IO](http://GPIO1.IO)\[0]                 |
| 47      | HDMI CON (J1)              | HDMI\_DDC\_SDA                                         | NC                                                     | HDMI\_DDC\_SDA                                |   | 48      | GND                        | GND                                                      | GND                                                      | GND                                                     |
| 49      | HDMI CON (J1)              | HDMI\_HPD                                              | TEST\_MODE                                             | HDMI\_HPD                                     |   | 50      | HEADER (CON4)              | SAI1\_RXD5, [GPIO4.IO](http://GPIO4.IO)\[7] (BT\_CFG5)   | SAI1\_RXD5, [GPIO4.IO](http://GPIO4.IO)\[7] (BT\_CFG5)   | USB2\_ID                                                |
| 51      | AUDIO CODEC                | SAI2\_TXC, [GPIO4.IO](http://GPIO4.IO)\[25]            | SAI2\_TXC, [GPIO4.IO](http://GPIO4.IO)\[25]            | SAI3\_TXC,[GPIO5.IO](http://GPIO5.IO)\[0]     |   | 52      | TERMINAL\_TX               | UART1\_TXD (Terminal), [GPIO5.IO](http://GPIO5.IO)\[23]  | UART2\_TXD (Terminal), [GPIO5.IO](http://GPIO5.IO)\[25]  | UART2\_TXD (Terminal), [GPIO5.IO](http://GPIO5.IO)\[25] |
| 53      | AUDIO CODEC                | SAI2\_TXD, [GPIO4.IO](http://GPIO4.IO)\[26]            | SAI2\_TXD, [GPIO4.IO](http://GPIO4.IO)\[26]            | SAI3\_TXD, [GPIO5.IO](http://GPIO5.IO)\[1]    |   | 54      | TERMINAL\_RX               | UART1\_RXD (Terminal), [GPIO5.IO](http://GPIO5.IO)\[22]  | UART2\_RXD (Terminal), [GPIO5.IO](http://GPIO5.IO)\[24]  | UART2\_RXD (Terminal), [GPIO5.IO](http://GPIO5.IO)\[24] |
| 55      | AUDIO CODEC                | SAI2\_TXFS, [GPIO4.IO](http://GPIO4.IO)\[24]           | SAI2\_TXFS, [GPIO4.IO](http://GPIO4.IO)\[24]           | SAI3\_TXFS, [GPIO4.IO](http://GPIO4.IO)\[31]  |   | 56      | NC                         | USB1\_ID                                                 | USB1\_ID                                                 | USB1\_ID                                                |
| 57      | AUDIO CODEC                | SAI2\_RXD, [GPIO4.IO](http://GPIO4.IO)\[23]            | SAI2\_RXD, [GPIO4.IO](http://GPIO4.IO)\[23]            | SAI3\_RXD, [GPIO4.IO](http://GPIO4.IO)\[30]   |   | 58      | GND                        | GND                                                      | GND                                                      | GND                                                     |
| 59      | AUDIO CODEC                | SAI2\_MCLK, [GPIO4.IO](http://GPIO4.IO)\[27]           | SAI2\_MCLK, [GPIO4.IO](http://GPIO4.IO)\[27]           | SAI3\_MCLK, [GPIO5.IO](http://GPIO5.IO)\[2]   |   | 60      | USB-HUB                    | USB2\_RXP                                                | NC                                                       | USB2\_RXP                                               |
| 61      | GND                        | GND                                                    | GND                                                    | GND                                           |   | 62      | USB-HUB                    | USB2\_RXN                                                | NC                                                       | USB2\_RXN                                               |
| 63      | HEADER (CON4)              | SAI1\_RXD6, [GPIO4.IO](http://GPIO4.IO)\[8] (BT\_CFG6) | SAI1\_RXD6, [GPIO4.IO](http://GPIO4.IO)\[8] (BT\_CFG6) | SAI3\_RXC, [GPIO4.IO](http://GPIO4.IO)\[29]   |   | 64      | GND                        | GND                                                      | GND                                                      | GND                                                     |
| 65      | RESET-B                    | SYS\_nRST                                              | SYS\_nRST                                              | SYS\_nRST                                     |   | 66      | USB-HUB                    | USB2\_TXN                                                | NC                                                       | USB2\_TXN                                               |
| 67      | HEADER (CON4)              | SAI1\_RXD4, [GPIO4.IO](http://GPIO4.IO)\[6] (BT\_CFG4) | SAI1\_RXD4, [GPIO4.IO](http://GPIO4.IO)\[6] (BT\_CFG4) | ETH1\_TRX3\_P (Second ETH)                    |   | 68      | USB-HUB                    | USB2\_TXP                                                | NC                                                       | USB2\_TXP                                               |
| 69      | HEADER (CON4)              | SAI1\_RXC, [GPIO4.IO](http://GPIO4.IO)\[1]             | SAI1\_RXC, [GPIO4.IO](http://GPIO4.IO)\[1]             | ETH1\_TRX3\_N (Second ETH)                    |   | 70      | GND                        | GND                                                      | GND                                                      | GND                                                     |
| 71      | HEADER (CON4)              | SAI1\_RXFS,                                            | SAI1\_RXFS, [GPIO4.IO](http://GPIO4.IO)\[0]            | ETH1\_TRX2\_P (Second ETH)                    |   | 72      | HEADER (CON4)              | SAI1\_RXD2, [GPIO4.IO](http://GPIO4.IO)\[4] (BT\_CFG2)   | SAI1\_RXD2, [GPIO4.IO](http://GPIO4.IO)\[4] (BT\_CFG2)   | ETH1\_TRX1\_P (Second ETH)                              |
| 73      | MICRO-SD                   | SD2\_VSELECT, [GPIO1.IO](http://GPIO1.IO)\[4]          | USB2\_ID (Pull-Up, 3V3)                                | ETH1\_TRX2\_N (Second ETH)                    |   | 74      | HEADER (CON4)              | SAI1\_RXD3, [GPIO4.IO](http://GPIO4.IO)\[5] (BT\_CFG3)   | SAI1\_RXD3, [GPIO4.IO](http://GPIO4.IO)\[5] (BT\_CFG3)   | ETH1\_TRX1\_N (Second ETH)                              |
| 75      | GND                        | GND                                                    | GND                                                    | GND                                           |   | 76      | GND                        | GND                                                      | GND                                                      | GND                                                     |
| 77      | HDMI CON (J1)              | HDMI\_AUXP                                             | NC                                                     | EARC\_N\_HPD                                  |   | 78      | HEADER (CON4)              | SAI1\_RXD0, [GPIO4.IO](http://GPIO4.IO)\[2] (BT\_CFG0)   | SAI1\_RXD0, [GPIO4.IO](http://GPIO4.IO)\[2] (BT\_CFG0)   | ETH1\_TRX0\_P (Second ETH)                              |
| 79      | HDMI CON (J1)              | HDMI\_AUXN                                             | NC                                                     | EARC\_P\_UTIL                                 |   | 80      | HEADER (CON4)              | SAI1\_RXD1, [GPIO4.IO](http://GPIO4.IO)\[3] (BT\_CFG1)   | SAI1\_RXD1, [GPIO4.IO](http://GPIO4.IO)\[3] (BT\_CFG1)   | ETH1\_TRX0\_N (Second ETH)                              |

## J9 connector

| **PIN** | **HummingBoard Pulse 2.4**                         | **IMX8M rev 2.0**                              | **IMX8M Mini rev 1.2**                                      | **IMX8M Plus rev 1.0**                                   |   | **PIN** | **HummingBoard Pulse 2.4**   | **IMX8M rev 2.0**                                        | **IMX8M Mini rev 1.2**                                     | **IMX8M Plus rev 1.0**                          |
| ------- | -------------------------------------------------- | ---------------------------------------------- | ----------------------------------------------------------- | -------------------------------------------------------- | - | ------- | ---------------------------- | -------------------------------------------------------- | ---------------------------------------------------------- | ----------------------------------------------- |
| 1       | ETH-POE                                            | MDI\_TRXN3                                     | MDI\_TRXN3                                                  | MDI\_TRXN3                                               |   | 2       | GND                          | GND                                                      | GND                                                        | GND                                             |
| 3       | ETH-POE                                            | MDI\_TRXP3                                     | MDI\_TRXP3                                                  | MDI\_TRXP3                                               |   | 4       | USB-TYPE-A                   | USB1\_TXP                                                | NC                                                         | USB1\_TXP                                       |
| 5       | GND                                                | GND                                            | GND                                                         | GND                                                      |   | 6       | USB-TYPE-A                   | USB1\_TXN                                                | NC                                                         | USB1\_TXN                                       |
| 7       | ETH-POE                                            | MDI\_TRXN2                                     | MDI\_TRXN2                                                  | MDI\_TRXN2                                               |   | 8       | GND                          | GND                                                      | GND                                                        | GND                                             |
| 9       | ETH-POE                                            | MDI\_TRXP2                                     | MDI\_TRXP2                                                  | MDI\_TRXP2                                               |   | 10      | USB-TYPE-A                   | USB1\_RXP                                                | NC                                                         | USB1\_RXP                                       |
| 11      | GND                                                | GND                                            | GND                                                         | GND                                                      |   | 12      | USB-TYPE-A                   | USB1\_RXN                                                | NC                                                         | USB1\_RXN                                       |
| 13      | ETH-POE                                            | MDI\_TRXN1                                     | MDI\_TRXN1                                                  | MDI\_TRXN1                                               |   | 14      | GND                          | GND                                                      | GND                                                        |                                                 |
| 15      | ETH-POE                                            | MDI\_TRXP1                                     | MDI\_TRXP1                                                  | MDI\_TRXP1                                               |   | 16      | USB-TYPE-A                   | USB1\_DP                                                 | USB1\_DP                                                   | USB1\_DP                                        |
| 17      | GND                                                | GND                                            | GND                                                         | GND                                                      |   | 18      | USB-TYPE-A                   | USB1\_DN                                                 | USB1\_DN                                                   | USB1\_DN                                        |
| 19      | ETH-POE                                            | MDI\_TRXN0                                     | MDI\_TRXN0                                                  | MDI\_TRXN0                                               |   | 20      | GND                          | GND                                                      | GND                                                        | GND                                             |
| 21      | ETH-POE                                            | MDI\_TRXP0                                     | MDI\_TRXP0                                                  | MDI\_TRXP0                                               |   | 22      | USB-HUB                      | USB2\_DP                                                 | USB2\_DP                                                   | USB2\_DP                                        |
| 23      | GND                                                | GND                                            | GND                                                         | GND                                                      |   | 24      | USB-HUB                      | USB2\_DN                                                 | USB2\_DN                                                   | USB2\_DN                                        |
| 25      | ETH-LED                                            | LED\_10\_100\_LED\_1000                        | LED\_10\_100\_LED\_1000                                     | LED\_0/PHY\_CFG0                                         |   | 26      | GND                          | GND                                                      | GND                                                        | GND                                             |
| 27      | ETH-LED                                            | LED\_ACT                                       | LED\_ACT                                                    | LED1\_0/PHY\_CFG0                                        |   | 28      | M.2\_GPS\_EN#                | USB\_H1\_PWR\_EN, [GPIO3.IO](http://GPIO3.IO)\[4]        | SAI5\_RXFS,[GPIO3.IO](http://GPIO3.IO)\[19]                | M.2\_GPS\_EN#, [GPIO1.IO](http://GPIO1.IO)\[07] |
| 29      | HEADER (CON4)                                      | PPS (Eth PHY)                                  | PPS (Eth PHY)                                               | NC                                                       |   | 30      | J9-59 (BT\_FW\_FLASH, J9-59) | USB\_OTG\_PWR\_EN, [GPIO3.IO](http://GPIO3.IO)\[2]       | SPDIF\_EXT\_CLK, [GPIO5.IO](http://GPIO5.IO)\[05]          | NC                                              |
| 31      | MIPI-DSI, ETH-NIC, DSI-CON, CSI-CON, RTC, MIKROBUS | I2C3\_SCL                                      | I2C3\_SCL                                                   | I2C3\_SCL                                                |   | 32      | MIKROBUS (J8-3)              | ECSPI2\_SS0, [GPIO5.IO](http://GPIO5.IO)\[13]            | ECSPI2\_SS0, [GPIO5.IO](http://GPIO5.IO)\[13] (UART4\_RTS) | ECSPI2\_SS0, [GPIO5.IO](http://GPIO5.IO)\[13]   |
| 33      | MIPI-DSI, ETH-NIC, DSI-CON, CSI-CON, RTC, MIKROBUS | I2C3\_SDA                                      | I2C3\_SDA                                                   | I2C3\_SDA                                                |   | 34      | CSI-CON (J19) or DSI-HDMI    | [GPIO5.IO](http://GPIO5.IO)\[6]                          | PDM\_DATA1, [GPIO3.IO](http://GPIO3.IO)\[22]               | NC                                              |
| 35      | GND                                                | GND                                            | GND                                                         | GND                                                      |   | 36      | GND                          | GND                                                      | GND                                                        | GND                                             |
| 37      | USB\_HUB\_CH1\_PWR\_EN                             | CSI\_nRST, [GPIO1.IO](http://GPIO1.IO)\[6]     | TCPC\_Nint1, [GPIO2.IO](http://GPIO2.IO)\[11]               | USB\_HUB\_CH1\_PWR\_EN, [GPIO1.IO](http://GPIO1.IO)\[14] |   | 38      | MICRO-SD                     | SD2\_CLK, [GPIO2.IO](http://GPIO2.IO)\[13]               | SD2\_CLK, [GPIO2.IO](http://GPIO2.IO)\[13]                 | SD2\_CLK, [GPIO2.IO](http://GPIO2.IO)\[13]      |
| 39      | J9-55 (BT\_FW\_FLASH, J9-55)                       | AUD\_nMUTE, [GPIO1.IO](http://GPIO1.IO)\[8]    | PDM\_DATA0, [GPIO3.IO](http://GPIO3.IO)\[21]                | NC                                                       |   | 40      | MICRO-SD                     | SD2\_CMD, [GPIO2.IO](http://GPIO2.IO)\[14]               | SD2\_CMD, [GPIO2.IO](http://GPIO2.IO)\[14]                 | SD2\_CMD, [GPIO2.IO](http://GPIO2.IO)\[14]      |
| 41      | ETH-NIC RST# (Intel, U6)                           | CLKO\_25MHz, [GPIO3.IO](http://GPIO3.IO)\[11]  | PDM\_CLK, [GPIO3.IO](http://GPIO3.IO)\[20]                  | NC                                                       |   | 42      | MICRO-SD                     | SD2\_DATA0, [GPIO2.IO](http://GPIO2.IO)\[15]             | SD2\_DATA0, [GPIO2.IO](http://GPIO2.IO)\[15]               | SD2\_DATA0, [GPIO2.IO](http://GPIO2.IO)\[15]    |
| 43      | USB1\_VBUS                                         | USB1\_VBUS                                     | USB1\_VBUS                                                  | USB1\_VBUS\_5V                                           |   | 44      | MICRO-SD                     | SD2\_DATA1, [GPIO2.IO](http://GPIO2.IO)\[16]             | SD2\_DATA1, [GPIO2.IO](http://GPIO2.IO)\[16]               | SD2\_DATA1, [GPIO2.IO](http://GPIO2.IO)\[16]    |
| 45      | MIKROBUS (J8-5)                                    | ECSPI2\_MISO, [GPIO5.IO](http://GPIO5.IO)\[12] | ECSPI2\_MISO, [GPIO5.IO](http://GPIO5.IO)\[12] (UART4\_CTS) | ECSPI2\_MISO, [GPIO5.IO](http://GPIO5.IO)\[12]           |   | 46      | MICRO-SD                     | SD2\_DATA2, [GPIO2.IO](http://GPIO2.IO)\[17]             | SD2\_DATA2, [GPIO2.IO](http://GPIO2.IO)\[17]               | SD2\_DATA2, [GPIO2.IO](http://GPIO2.IO)\[17]    |
| 47      | MIKROBUS (J8-6)                                    | ECSPI2\_MOSI, [GPIO5.IO](http://GPIO5.IO)\[11] | ECSPI2\_MOSI, [GPIO5.IO](http://GPIO5.IO)\[11] (UART4\_TXD) | ECSPI2\_MOSI,[GPIO5.IO](http://GPIO5.IO)\[11]            |   | 48      | MICRO-SD                     | SD2\_DATA3, [GPIO2.IO](http://GPIO2.IO)\[18]             | SD2\_DATA3, [GPIO2.IO](http://GPIO2.IO)\[18]               | SD2\_DATA3, [GPIO2.IO](http://GPIO2.IO)\[18]    |
| 49      | MIKROBUS (J8-4)                                    | ECSPI2\_SCLK, [GPIO5.IO](http://GPIO5.IO)\[10] | ECSPI2\_SCLK, [GPIO5.IO](http://GPIO5.IO)\[10] (UART4\_RXD) | ECSPI2\_SCLK, [GPIO5.IO](http://GPIO5.IO)\[10]           |   | 50      | MICRO-SD                     | SD2\_NCD, [GPIO2.IO](http://GPIO2.IO)\[12]               | SD2\_NCD, [GPIO2.IO](http://GPIO2.IO)\[12]                 | SD2\_NCD, [GPIO2.IO](http://GPIO2.IO)\[12]      |
| 51      | AUD\_CODEC, USB-TYPEC, USB-HUB                     | I2C2\_SDA                                      | I2C2\_SDA                                                   | I2C2\_SDA                                                |   | 52      | USB-HUB                      | USB2\_VBUS                                               | USB2\_VBUS                                                 | USB2\_VBUS\_3V3                                 |
| 53      | AUD\_CODEC, USB-TYPEC, USB-HUB                     | I2C2\_SCL                                      | I2C2\_SCL                                                   | I2C2\_SCL                                                |   | 54      | HEADER, DIP-SW               | SAI1\_TXD5,[GPIO4.IO](http://GPIO4.IO)\[17] (BT\_CFG13)  | SAI1\_TXD5, [GPIO4.IO](http://GPIO4.IO)\[17] (BT\_CFG13)   | SAI5\_MCLK, [GPIO3.IO](http://GPIO3.IO)\[25]    |
| 55      | BT-FW\_FLASH (J9-39)                               | SWDCLK1 (BT Flash)                             | NC                                                          | SAI5\_RXC, [GPIO3.IO](http://GPIO3.IO)\[20]              |   | 56      | NC                           | NC                                                       | SAI5\_MCLK, [GPIO3.IO](http://GPIO3.IO)\[25]               | SAI5\_RXD3, [GPIO3.IO](http://GPIO3.IO)\[24]    |
| 57      | HEADER (CON4)                                      | CLK\_25M (Eth PHY)                             | CLK\_25M (Eth PHY)                                          | SAI5\_RXD2, [GPIO3.IO](http://GPIO3.IO)\[23]             |   | 58      | NC                           | NC                                                       | PDM\_DATA2, [GPIO3.IO](http://GPIO3.IO)\[23]               | NC                                              |
| 59      | BT-FW\_FLASH (J9-30)                               | SWDIO1 (BT Flash)                              | NC                                                          | NC                                                       |   | 60      | NC                           | NC                                                       | PDM\_DATA3, [GPIO3.IO](http://GPIO3.IO)\[24]               | WDOG\_B, [GPIO1.IO](http://GPIO1.IO)\[02]       |
| 61      | MICRO-SD                                           | NVCC\_SD2                                      | SPDIF\_RX, [GPIO5.IO](http://GPIO5.IO)\[4]                  | NC                                                       |   | 62      | PUSH-B                       | ONOFF                                                    | ONOFF                                                      | ONOFF                                           |
| 63      | 3V3\_IN                                            | 3V3\_OUT                                       | 3V3\_OUT                                                    | 3V3\_OUT                                                 |   | 64      | HEADER, DIP-SW               | SAI1\_TXD6, [GPIO4.IO](http://GPIO4.IO)\[18] (BT\_CFG14) | SAI1\_TXD3, [GPIO4.IO](http://GPIO4.IO)\[15] (BT\_CFG11)   | NC                                              |
| 65      | 3V3\_IN                                            | 3V3\_OUT                                       | 3V3\_OUT                                                    | 3V3\_OUT                                                 |   | 66      | NC                           | NC                                                       | SAI3\_TXD, [GPIO5.IO](http://GPIO5.IO)\[1]                 | VSD\_3V3 (uSD power for next HBP)               |
| 67      | 3V3\_IN                                            | 3V3\_OUT                                       | 3V3\_OUT                                                    | 3V3\_OUT                                                 |   | 68      | MICRO-SD                     | PWM2\_OUT, [GPIO1.IO](http://GPIO1.IO)\[13]              | SD2\_nRST, [GPIO2.IO](http://GPIO2.IO)\[19]                | SD2\_RESET\_B, [GPIO2.IO](http://GPIO2.IO)\[19] |
| 69      | 3V3\_IN                                            | 3V3\_OUT                                       | NC                                                          | 3V3\_OUT                                                 |   | 70      | GND                          | GND                                                      | GND                                                        | GND                                             |
| 71      | VIN\_5V0                                           | VIN\_5V0                                       | VIN\_5V0                                                    | VIN\_5V0                                                 |   | 72      | GND                          | GND                                                      | GND                                                        | GND                                             |
| 73      | VIN\_5V0                                           | VIN\_5V0                                       | VIN\_5V0                                                    | VIN\_5V0                                                 |   | 74      | GND                          | GND                                                      | GND                                                        | GND                                             |
| 75      | VIN\_5V0                                           | VIN\_5V0                                       | VIN\_5V0                                                    | VIN\_5V0                                                 |   | 76      | GND                          | GND                                                      | GND                                                        | GND                                             |
| 77      | VIN\_5V0                                           | VIN\_5V0                                       | VIN\_5V0                                                    | VIN\_5V0                                                 |   | 78      | GND                          | GND                                                      | GND                                                        | GND                                             |
| 79      | VIN\_5V0                                           | VIN\_5V0                                       | VIN\_5V0                                                    | VIN\_5V0                                                 |   | 80      | GND                          | GND                                                      | GND                                                        | GND                                             |

## mikroBUS connector

| **HummingBoard Pulse 2.4** | **IMX8M rev 2.0**                              | **IMX8M Mini rev 1.2**                                      | **IMX8M Plus rev 1.0**                         |
| -------------------------- | ---------------------------------------------- | ----------------------------------------------------------- | ---------------------------------------------- |
| MIKROBUS (J8-2)            | SAI2\_RXD, [GPIO4.IO](http://GPIO4.IO)\[23]    | SAI2\_RXD, [GPIO4.IO](http://GPIO4.IO)\[23]                 | SAI3\_RXD, [GPIO4.IO](http://GPIO4.IO)\[30]    |
| MIKROBUS (J8-3)            | ECSPI2\_SS0, [GPIO5.IO](http://GPIO5.IO)\[13]  | ECSPI2\_SS0, [GPIO5.IO](http://GPIO5.IO)\[13] (UART4\_RTS)  | ECSPI2\_SS0, [GPIO5.IO](http://GPIO5.IO)\[13]  |
| MIKROBUS (J8-4)            | ECSPI2\_SCLK, [GPIO5.IO](http://GPIO5.IO)\[10] | ECSPI2\_SCLK, [GPIO5.IO](http://GPIO5.IO)\[10] (UART4\_RXD) | ECSPI2\_SCLK, [GPIO5.IO](http://GPIO5.IO)\[10] |
| MIKROBUS (J8-5)            | ECSPI2\_MISO, [GPIO5.IO](http://GPIO5.IO)\[12] | ECSPI2\_MISO, [GPIO5.IO](http://GPIO5.IO)\[12] (UART4\_CTS) | ECSPI2\_MISO, [GPIO5.IO](http://GPIO5.IO)\[12] |
| MIKROBUS (J8-6)            | ECSPI2\_MOSI, [GPIO5.IO](http://GPIO5.IO)\[11] | ECSPI2\_MOSI, [GPIO5.IO](http://GPIO5.IO)\[11] (UART4\_TXD) | ECSPI2\_MOSI,[GPIO5.IO](http://GPIO5.IO)\[11]  |
|                            |                                                |                                                             |                                                |
| MIKROBUS (J10-1)           | UART3\_CTS, [GPIO5.IO](http://GPIO5.IO)\[8]    | UART1\_CTS, [GPIO5.IO](http://GPIO5.IO)\[26]                | UART3\_CTS, [GPIO5.IO](http://GPIO5.IO)\[8]    |
| MIKROBUS (J10-2)           | UART3\_RTS, [GPIO5.IO](http://GPIO5.IO)\[9]    | UART1\_RTS, [GPIO5.IO](http://GPIO5.IO)\[27]                | UART3\_RTS, [GPIO5.IO](http://GPIO5.IO)\[9]    |
| MIKROBUS (J10-3)           | UART3\_RXD, [GPIO5.IO](http://GPIO5.IO)\[26]   | UART1\_RXD, [GPIO5.IO](http://GPIO5.IO)\[22]                | UART3\_RXD, [GPIO5.IO](http://GPIO5.IO)\[6]    |
| MIKROBUS (J10-4)           | UART3\_TXD, [GPIO5.IO](http://GPIO5.IO)\[27]   | UART1\_TXD, [GPIO5.IO](http://GPIO5.IO)\[23]                | UART3\_TXD, [GPIO5.IO](http://GPIO5.IO)\[7]    |
| MIKROBUS (J10-5)           | I2C3\_SCL                                      | I2C3\_SCL                                                   | I2C3\_SCL                                      |
| MIKROBUS (J10-6)           | I2C3\_SDA                                      | I2C3\_SDA                                                   | I2C3\_SDA                                      |


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