The Linux BSP (Board Support Package) for the NXP i.MXRT 1170 SoC is compatible with the following NXP EVK boards:

• IMXRT1170-EVK
• IMXRT1170-EVKB.

This application note explains specifics of support for the EVKB board, as compared to the EVK board.

EVKB Differences Affecting Linux BSP

Support for Ethernet

In the EVKB hardware design, there is a conflict between ENET_MDC and the SD Card Detect signal. Details are as follows:

• On MIMXRT1170-EVK/EVKB boards, the GPIO_AD_32 signal, used as ENET_MDC, can be also multiplexed to the SD1_CD_B. This is controlled by the on-board R1926 and R136 resistors.
• On the IMXRT1170-EVKB REVC board, the R136 resistor is populated by default, which means the ENET1 controller is unable to access the Ethernet PHY if an SD Card is inserted into the SD Card slot.
  To address this issue case, remove the R136 resistor to allow network operations over the 100M Ethernet interface.
• The Linux BSP does not use SD1_CD_B. This is true for both U-Boot and the Linux kernel. This implies that removing the R136 resistor does not affect SD Card operation in Linux.
• The above notwithstanding, there could be an issue with booting from certain SD Cards, since the internal i.MX RT1170 Boot-ROM loader sometimes failed to correctly detect an SD Card insertion without SD1_CD_B. In our testing, this affects only a certain class of SD Cards (presumably, lower class cards). Booting from other SD Cards is possible even with the R136 resistor removed.

Different Naming for Connectors

The IMXRT1170-EVKB board makes use of different names for some on-board connectors. This affects the Emcraft user documentation, in the sense that using the EVKB board, naming of the connectors may be different in some situations, as compared to what is stated in the Emcraft user documentation (the on-line Application Notes). Details are as follows:

• The micro USB debug port used for the serial console is named as J86;
• The 100M ethernet connector is named as J32;
• The USB OTG port 1 is named as J20;
• The USB OTG port 2 is named as J18;
• The CAN Bus connector CAN3 is named as J47.