[Coco] SuperIDE / HDB-DOS and physical floppies question

Steven Hirsch snhirsch at gmail.com
Wed Jul 11 18:03:21 EDT 2012

On Wed, 11 Jul 2012, tonym wrote:

> I was thinking of maybe splurging for one of these:
> http://www.ebay.com/itm/Willem-EPROM-Programmer-Pro-Version-PCB-ver-5-5-PIC-/150853071132?pt=LH_DefaultDomain_0&hash=item231f8b311c
> No switches, all software... Or maybe a USB variant:
> http://www.ebay.com/itm/NEWEST-PCB6-0-USB-Willem-EPROM-Programmer-PIC-BIOS-AVR-Ship-from-USA-/310412788418?pt=LH_DefaultDomain_0&hash=item48460b42c2

The latter one might be a safer bet unless you're sure you'll have a box 
with a parallel port around for the near future.

Also, the Willem units really fall on their faces trying to program older 
NMOS EPROMS that require 21V and 25V Vpp.  These include 2708, 2716, 2732 
(not the 'A' version).  There's a DC-to-DC converter that kinda, sorta 
tries to boost the +5V power up to the requisite level, but it's very shy 
on current capacity and does not do a robust job.

I modded mine with a relay and external power input for the older parts 
before mothballing it in favor of an Andromeda unit (needed to program 
bipolar PROMs).



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