I have 5 chips (FE310-G002) and I would like to build 5 PCBs with this chip.
Its for a university project to test RISC-V chips with JTAG.
I also have for testing and troubleshooting a HiFive1 Rev B board and a Sparkfun Red V board (very similar to the HIFive1).
Looking at both schematics (for HiFive1 and RedV) I see there is a USB-JTAG IC which works great and I can debug perfectly using openOCD.
But on my final board I want to use a third party tool (BusPirate) which is also a USB-JTAG and it is supported by OpenOCD.
My idea is to create a small board with the FE310-G002 , the Quad SPI memory, power regulators ICs and a lot of GPIO pins. I plan to leave the JTAG pins (we have FPGA programming experience so we have dealt with JTAG before) accesible so we can connect with the USB-JTAG interface.
So here is the question… I see that both the HIFive1 and RedV board have the JTAG pins accesible, but they are connected both to the FE310-G002 and the USB-JTAG IC.
I want to know if I can connect in parallel my own USB-JTAG and simply skip using the onboard USB-JTAG IC.
The idea is to test this BusPirate with OpenOCD before manufacturing the PCBs with the FE310-G002 on them.