Amiga 500 with Supradrive Keyboard Issues

[Sargie]

Hey Guys and Gals,

I am hoping one of your knowledgable people might have some insight into this issue:

I recently sold a Supradrive 500 and Interface to a chap. It worked fine when it left my house. He's got it and whenever the drive is connected to his Amiga 500 (with 1MB RAM, Kickstart 1.3) the keyboard does not function.

This is what is happening in his words:

"I'm turning the SupraDrive on before I turn on the computer. It boots up to the Workbench with the hard drive connected, but during the boot up process - pretty much a second or two after you turn on the computer, and what seems like before anything really starts to load - and after Workbench loads, the caps lock key flashes and the keyboard doesn't work. It does this whether Workbench loads from the hard disk or a floppy. If the hard drive and interface isn't plugged in, the computer works perfectly."

Any ideas much appreciated before I pay to have this sent back!

Many kind regards,

Sarge

[Toni Wilen]

Power supply problem? (does it work if harddrive is removed?) Keyboard bending slightly when Supradrive is inserted and cracked solder joint opens or shorts?

Flashing caps lock means keyboard microcontroller detected an error condition. (for example internal rom error or shorted keyboard matrix lines, count the number of flashes between longer pause)

[Sargie]

Hi Tony,

Thanks for the reply.

It DOES work when the hard-drive is removed. The hard drive has it's own PSU though... Would that make a difference if the problem is with the computer PSU?

Thanks!

Sarge

[rkauer]

Ask him to check inside the expansion: most controllers have an option to use the Amiga slot to power (via a pair of jumpers) or not.

Two power supplies in tandem is not a good thing, as they surely have slightly different voltages and so a current flow from one to another, adding ripple to the Amiga bus.