Speed Issue

[itisdeadjim]

Got a new Revelprog, installed latest firmware+software.
I have some odd speed issue. At first it was constantly dumping at low speed (ca 300kbit/s) no matter what setting I used. Then it switched for whatever reason and now is constantly at 8-9MB/s.
The self test was OK. I could dump smaller SPI chips with either speed. But I got problems with larger ones. Not sure if this is only a speed issue, since it is ISP it could also be other reasons. But changing clock speed sometimes helped in these cases.
I also tried to reinstall drivers. It is a Windows 11 machine and the libusb-win32 driver failed. Not sure if this is an issue, since Zadig should be used for installation which worked fine.
Any ideas?

[ArT]

Without correct driver it will not work at all.

For full speed 8-9mbps SCK minimum 50% is required.

Are you using any emulation or HUB for USB? It may cause hardware delays.

And additional hint - there are few types of general SPI Flash ended with [PP], [BP] or without sufix - please select [PP] (Page Program) for fastest operation, because [BP] (byte programm) is compatible mode (for some devices) and it's much slower.