Dear Seeed Studio team,
Thank you for your support.
The customer purchased 114992325 Dev. board for one pc.
But he claimed V1.2 has initial defect.
I see the topic for this failure on Interface magazine in Japan as well.
https://interface.cqpub.co.jp/gowin-runberv1-2/
The problem is inposible flashing the internal flash memory.
[Details]
- This board includes FPGA GW1N-UV4LQ144（Gowin）which has Configuration flash memory.
But this Version 1.2 has defective converting circuit for USB-JTAG.
So, It will be fail flashing the Internal flash memory when try to write flash memory and even not only flash memory.
Impossible to write SRAM, nither.
But previous Version 1.1 is working fine.
- The cause
Version 1.1 was used FT232HQ（FTDI）as USB-JTAG interface.
But Ver. 1.2 is changed to CH552T（Nanjing Qinheng Microelectronics）.
FT232HQ has MPSSE system which able to communicate SPI or JTAG protocol signal through USB.
difference is CH552T has USB device system CPU. So, USB-JTAG convert system is built in as software.
But problem is clock.
GW1N-UV4 flash memory requires to apply TCK clock 1M ～ 5MHz / 120ms to out continuously.
But Ver. 1.2 has gap between 8th clock is 12.96us each.
That’s the reason fail to flash the internal flash memory.
(Can’t upload the photo Cause Im new user. I will put it after 21 hours as reply)
And even It’s impossible to supplier to give update the firmware for this case to fix creating stronger signal.
Because CPU core spec isn’t enough of CH552T.
The question is,
- Is Ver. 1.2 defect known issue?
Could you give us some advice?
Thank you so much.
Kind Regards,
Takashi
T4489841
