Hi,
If you prefer debug via UART, you might try to find out it from main board.
But since the label of J46 on mainbaord is incorrect, so, nothing will be printed when boot up.
After investigated, finally, the label is inverted.
For more detailed information, please refer to the following:
https://steward-fu.github.io/website/handheld/gameshell/uart.htm
Pin you need for UART debug:
GND
UART TX => PB0 (UART0_TX)
UART RX => PB1 (UART0_RX)
schematic from clockworkpi github:
UART debug port located on J46
J46 on mainboard
3.3V USB to UART
connect it but nothing happen when booting
GND pin
https://steward-fu.github.io/website/handheld/gameshell/uart/6.jpg
invert direction (pin1 => schematic p14, pin14 => schematic p1)
U-Boot SPL 2018.01-rc1-00116-g214ced3654 (Jun 08 2018 - 16:32:06)
DRAM: 512 MiB
Trying to boot from MMC1
U-Boot 2018.01-rc1-00116-g214ced3654 (Jun 08 2018 - 16:32:06 +0800) Allwinner Technology
CPU: Allwinner A33 (SUN8I 1667)
Model: clockworkpi CPI3
DRAM: 512 MiB
MMC: SUNXI SD/MMC: 0, SUNXI SD/MMC: 1
Card did not respond to voltage select!
mmc_init: -95, time 22
*** Warning - MMC init failed, using default environment
Setting up a 320x240 lcd console (overscan 0x0)
