USBasp bitclock rate ...

Hi,

I am using Arduino v1.8.5 and a USBASP programmer to upload a large program into a Mega2560 via the ISP port (I cannot use the USB port for a variety of reasons).

The problem is it takes a long time to upload, much longer than via the USB port.

I have updated the USBasp firmware so that it can accept commands to vary the bitrate (Avrdude uses the -B command) but it didnt change the upload speed.

I could use AVRDUDESS and set the speed in its GUI but I would rather use the USBasp via the Ardhuino IDE.

Where do I set the speed to use in the IDE ???

Web searches have revealed a variety of supposed solutions, but none of them seem to make a difference.

TIA
Dave