Raspi3 Raspi4 jtag debug

40-pin gpio connect

gpio22-27 Alternative Function Assignments all are ALT4.

connect following gpio pin to jlink pin.

管脚名字	gpio功能ALT4
GPIO22	ARM_TRST
GPIO23	ARM_RTCK
GPIO24	ARM_TDO
GPIO25	ARM_TCK
GPIO26	ARM_TDI
GPIO27	ARM_TMS
GPIO01	Vref
GPIO09	GND

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Download pre-built OpenOCD for Windows

https://gnutoolchains.com/arm-eabi/openocd/