trying to connect my Maix Go to an RV Debugger

Hello!

I am trying to connect my Maix Go to an RV Debugger. I got to the point, that the PC (Windows) tools try to communicate with the Maix Go board, but it never works, because it seems that Maix Go pulls down the TCK pin.

The pictures top to bottom (because as a new user I can only insert one picture per post):

  1. Fist, I connect the RV Debugger see below (black is GND, orange is TCK):
  2. Then I short the DFU pins, as was mentioned on this page (the 3 blue leds start flowing from right to left):
    https://blog.sipeed.com/p/727.html
  3. Then I connect the RV Debugger to the pins below (note that it does not change anything if I connect only GND and TCK):
  4. When TCK is connected, I get the following logic analyzer capture (both using openocd or platformio):
  5. When TCK is not connected, I get the following logic analyzer capture:

Now, what should I do for TCK not being pulled down?
6. The Sipeed MaixGO Datasheet v1.1 says the following:
It talks about a pull down resistor, and FCC certification. I have 3 Maix Go boards, bought a year ago, in 2 different times. I have tested two of them with the same result. Can it be, that I have the wrong boards?

This is the error:
bin\openocd -f bin\kendryte_ftdi.cfg -m0


| |/ /___ _ __ | | __ _ | | ___
| ’ // _ \ ’
\ / ` | '__| | | | __/ _
| . \ __/ | | | (
| | | | || | || __/
|
|__|| ||_,|| _, |___|
|___/
Kendryte Open On-Chip Debugger For RISC-V v0.2.3 (2019-02-21)
Licensed under GNU GPL v2
ftdi samples TDO on falling edge of TCK
adapter speed: 10 kHz
Info : clock speed 10 kHz
Error: JTAG scan chain interrogation failed: all ones
Error: Check JTAG interface, timings, target power, etc.
Error: Trying to use configured scan chain anyway…
Error: riscv.cpu: IR capture error; saw 0x1f not 0x01
Warn : Bypassing JTAG setup events due to errors
Error: Unsupported DTM version: 15
Info : Listening on port 3333 for gdb connections
Error: Target not examined yet

Connect Sipeed RV Debugger and K210 development board according to the following table

**Note: **

​ Because the data rate used in debugging is higher, it is necessary to use twisted pair to wind TDO and GND to reduce interference

After run OpenOCD

config file of OpenOCD:

  • jink
    ` # debug adapter
    interface jlink

transport select jtag
adapter_khz 3000

server port

gdb_port 3333
telnet_port 4444

add cpu target

set _CHIPNAME riscv

jtag newtap $_CHIPNAME cpu -irlen 5 -expected-id 0x04e4796b

set _TARGETNAME $_CHIPNAME.cpu
target create $_TARGETNAME riscv -chain-position $_TARGETNAME

command

init
halt
`
Sipeed rv debugger

`# interface ftdi

# for canaan’s ftdi

ftdi_vid_pid 0x0403 0x6010 00

ftdi_layout_init 0x00e8 0x00eb

transport select jtag

ftdi_tdo_sample_edge falling

adapter_khz 64000

gdb_port 3333

telnet_port 4444

set _CHIPNAME riscv

jtag newtap $_CHIPNAME cpu -irlen 5 -expected-id 0x04e4796b

set _TARGETNAME $_CHIPNAME.cpu

target create $_TARGETNAME riscv -chain-position $_TARGETNAME

init

halt

debug adapter

interface ftdi
#jlink serial 000504401724

#source [find ./tcl/interface/ftdi/opendous_ftdi.cfg]
ftdi_vid_pid 0x0403 0x6010

#ftdi_layout usbjtag
ftdi_channel 0
ftdi_layout_init 0x08 0x0b
ftdi_layout_signal nTRST -data 0x10
ftdi_layout_signal nRST -oe 0x40

transport select jtag
adapter_khz 300

server port

gdb_port 3333
telnet_port 4444

add cpu target

set _CHIPNAME riscv

jtag newtap $_CHIPNAME cpu -irlen 5 -expected-id 0x04e4796b

set _TARGETNAME $_CHIPNAME.cpu
target create $_TARGETNAME riscv -chain-position $_TARGETNAME

command

init
halt
`