REL1.0
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i.MX8 SMARC SOM Hardware User Guide
iWave Systems Technologies Pvt. Ltd.
2.9.2
Debug Header (Optional)
The i.MX8 SMARC SOM optionally supports one JTAG interface and/or UART interface for CPU debug purpose over a
customized 20-pin connector (J3
). Even though this JTAG connector pinout is fully compatible with “ARM JTAG 20”
connector, the physical dimension of connector is made smaller because of space constraint. i.MX8
CPU’s JTAG pins
are 1.8V tolerant and so 1.8V reference power is provided to pin 1 of the connectors to allow JTAG tool to automatically
configure the logic signals for the right voltage.
The i.
MX8 CPU’s SCU_UART0
and M4 Core1 UART or UART4 can be taken out from J3 header and using 1.8V voltage
level FTDI’s UART to USB smart cable (
TTL-232RG-VREG1V8-WE)
UART can be directly connected to Host PC for
debugging.
Debug Header (J3) is physically located on topside of the SOM. This is the optional feature and will not be populated
in default configuration.
Number of Pins
- 20
Connector Part
- GRPB102MWCN-RC from Sullins Connector Solutions
Mating Connector
- LPPB102CFFN-RC from Sullins Connector Solutions
Figure 7: Debug Header