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| author | Luke T. Shumaker <lukeshu@lukeshu.com> | 2024-11-15 00:14:31 -0700 |
|---|---|---|
| committer | Luke T. Shumaker <lukeshu@lukeshu.com> | 2024-11-19 20:15:16 -0700 |
| commit | 573b0f7d4d4a7e84ae8d1e4a7c0611dd9f513fa2 (patch) | |
| tree | b0396c6f2d721c7c31bcff68272e676662c3e510 /README.md | |
| parent | 0011fcb2328cf387225a72eee7bdc3d8ea31d71d (diff) | |
README: Add notes about SWD
Diffstat (limited to 'README.md')
| -rw-r--r-- | README.md | 103 |
1 files changed, 102 insertions, 1 deletions
@@ -32,7 +32,108 @@ UART: - pin1: gpio0: TX (so connect it to your FTDI's RX) - pin2: gpio1: RX (so connect it to your FTDI's TX) - pin3: gnd (so connect it to your FTDI's GND) -- picocom --baud=115200 /dev/ttyUSB0 +- `picocom --baud=115200 /dev/ttyUSB0` +- `picocom --baud=115200 /dev/ttyACM0` + +- `openocd -f interface/cmsis-dap.cfg -f target/rp2040.cfg -c "adapter speed 5000"` +- `arm-none-eabi-gdb ./build/rp2040/cmd/sbc_harness/sbc_harness.elf` + ``` + target remote localhost:3333 + monitor reset init + continue + ``` + +SWD: +- https://www.raspberrypi.com/documentation/microcontrollers/debug-probe.html +- https://github.com/raspberrypi/debugprobe +- https://developer.arm.com/documentation/101451/0100/About-CMSIS-DAP + +## Raspberry Pi 3-pin Debug Connector +- https://datasheets.raspberrypi.com/debug/debug-connector-specification.pdf + +| Pin # | UART | ARM SW-DP | cJTAG (IEEE 1149.7) | +|-------|----------------------|------------------------------------|----------------------------------| +| 1 | RX (targetâdebugger) | SC/SWCLK (serial clock) | TMSC - Test Clock Control | +| 2 | GND | GND | GND | +| 3 | TX (targetâdebugger) | SD/SWDIO (bidi serial data) | TCKC - Test Master/Slave Control | +| | | SWO (optional: serial wire output) | | + +## UART (Universal asynchronous receiver/transmitter) + +## ARM SWD (Serial Wire Debug) +- https://developer.arm.com/documentation/101761/1-0/Debug-and-trace-interface/Serial-Wire-Debug-signals +- https://developer.arm.com/documentation/ihi0031/a/The-Serial-Wire-Debug-Port--SW-DP-/Introduction-to-the-ARM-Serial-Wire-Debug--SWD--protocol +- https://arm-software.github.io/CMSIS-DAP/latest/index.html +- ADIv5: https://developer.arm.com/documentation/ihi0031/g/ +- ADIv6: https://developer.arm.com/documentation/ihi0074/e/ + +Alternative to Raspberry Pi Debug Probe: +https://oshwlab.com/wagiminator/samd11c-swd-programmer which uses +https://github.com/ataradov/free-dap instead of ARM's reference CMSIS +implementation + +Note that the RP2040 chip has a pure SW-DP (just speaks SWD), not a +JTAG-DP (just speaks JTAG) or a SWJ-DP (can speak either SWD or JTAG). + +``` ++-[Host PC]-------------------------+ +| | +| +-----+ | +| | GDB | | +| +-----+ | +| ^ | +| | GDB Remote Serial Protocol +| | on localhost:3333 +| V | +| +---------+ | +| | OpenOCD | | +| +---------+ | +| ^ | +| | | ++-----------------|-----------------+ + USB-A + | + | ARM CMSIS-DAP protocol + | (a USB-based protocol) + | + (micro)USB-B + +-[Debug Probe]-------+ + | | | + | V | + | +----------------+ | + | | ARM's | | + | | reference | | + | | CMSIS-DAP | | + | | implementation | | + | +----------------+ | + | ^ | + | | | + +----------|----------+ + SW-DP (3-pin JST-SH) + | + | ADIv5 SWD protocol + | + SW-DP (3 .1" headers) ++-[SBC-Harness]---|-----------------+ +| | | +| ,---------------' | +| | | +| | +----------------------------+ | +| | | Cortex-M0+ | | +| | | +------------------------+ | | +| +--->| CoreSight ADIv5 module | | | +| | | +------------------------+ | | +| | +----------------------------+ | +| | | +| | +----------------------------+ | +| | | Cortex-M0+ | | +| | | +------------------------+ | | +| `--->| CoreSight ADIv5 module | | | +| | +------------------------+ | | +| +----------------------------+ | +| | ++-----------------------------------+ +``` # Usage |