ConnectCore 6UL SBC Pro interfaces
Debug interfaces
ConnectCore 6UL SBC Pro Hardware Reference Manual
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bits. If the boot configuration OTP bits are not programmed, the CPU falls back to booting into USB
debug mode.
The default state for the jumper is open, which configures the i.MX6UL to boot from board settings
(from NAND flash). If the NAND flash doesn't contain valid firmware, the i.MX6UL also falls back to
booting into USB debug mode. You can use this functionality for recovery purposes, such as if the boot
loader is erased or cannot boot.
For advanced functionality, the ConnectCore 6UL SBC Pro provides four resistors to configure the
SOM boot mode. For more information about boot mode configuration, please refer to the
ConnectCore for i.MX6UL system-on-module Hardware Reference Manual
The following table shows resistor configuration for the different boot modes:
R24
R25
R28
R29
Comment
Not populated Not populated Populated
Populated
Boot from fuses
Populated
Not populated Not populated Populated
Boot from serial downloader
Not populated Populated
Populated
Not populated Boot from board settings (default)
Populated
Populated
Not populated Not populated Reserved
Note
A different resistor configuration may prevent the ConnectCore 6UL module from booting.
Debug interfaces
JTAG
The ConnectCore 6UL SBC Pro provides a Tag Connect footprint for accessing the i.MX6UL JTAG debug
port. You can find this footprint on the bottom side of the board.
SWD
The ConnectCore 6UL SBC Pro provides two options for programming and debugging the MCA of the
ConnectCore 6UL module. The first option is a 2x5, 1.27 mm pitch pin header on the top side of the
board (which, by default, is not populated). The following table shows the pinout of the SWD connector.
Pin Signal name
Description
1
VCC_MCA
3.3V supply voltage of the MCA
2
MCA_SWD_DIO SWD bidirectional data pin
3
GND
Ground
4
MCA_SWD_CLK SWD clock signal
5
VCC_MCA
3.3V supply voltage of the MCA
6
NC
Not connected
7
NC
Not connected
