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pulp-platform / riscv-dbg

RISC-V Debug Support for our PULP RISC-V Cores
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TDO is driven on th rising edge of tck #173

Closed omerguzelelectronicguy closed 1 month ago

omerguzelelectronicguy commented 2 months ago

https://github.com/pulp-platform/riscv-dbg/blob/618ee6e0e2610ef47e0dcc4df6748af3dffff731/src/dmi_jtag_tap.sv#L202-L211 As I understand the jtag standarts tells that tdo should be driven in the falling edge of the tck. It is also left as comment in the code section above. However, It is driven in the rising edge. Did I misunderstand the standart? What am I missing? Or Is this just a small bug in the code?

omerguzelelectronicguy commented 1 month ago

I missed that it is driven in posedge of tck_n which is negedge of tck.