Ive been working on a test dev board for the stm32c011 with plans to use the wlcsp-12 package for the final product and have it be user programmable over USB/UART. I bought the following official ST micro dev board for it to be able to test the various connections like UART and SWD.
https://www.st.com/en/evaluation-tools/stm32c0116-dk.htmlWith the following schematics,
https://www.st.com/resource/en/schematic_pack/mb1684-c011f6-b01-schematic.pdfUsing the board as normal with the microcontroller daughterboard in the st-link board i can get it to connect perfectly fine with STM32CubeProgrammer, after changing one option bit to enable the boot0 pin i can still easily get it to connect to the ST-Link and now also over UART using a cp2102 with the daughter board in a breadboard and otherwise not connected to the st-link carrier
But my issue is im not sure what the st-link carrier is actually using as its protocol to connect, because to replicate i have to connect 5 pins T_JTMS, T_JTCK, T_NRST, T_VCP_TX and T_VCP_RX and then the daughter board connects to the st-link outside of the default socket. What i dont understand is that i have no idea what this protocol even really is, cause in the programmer software it selected to use SWD, but this is like JTAG, when selecting JTAG no connection is made. There are SWD pins SWDIO and SWCLK on the carrier board but connecting them to the daughter board externally yields no connection whatsoever.
What i want to be able to do on my dev board is to just connect SWDIO, SWCLK and use that for debug then be able to switch traces with jumpers and use UART instead for programming but i cant get the st-link carrier to connect over just SWD, is this is because of the st-link being built in? or should i expect the dev board st-link to act the same as any normal v2 st-link