Keith, at 21:08 on Mar 21 1996, you wrote to Bill Grimsley...

BG> What's the story with EPROM copying these days, do you need highly
BG> specialised equipment, or what?

KR> you need an eprom programmer, some are plugins to a pc others are
KR> standalone, usually with an rs232 port. you also need a uv source of the
KR> correct wavelength to erase the eprom first.

The EPROMs I had in mind are probably only electrically erasable (if at
all) as they have no window on them.  An EEPROM perhaps?  I also presume
that some of them are only programmable the once, and can't be erased after
that, right?

BG> The Sportie's EPROM appears to be a fairly standard 256Kb job, and
BG> I wonder, do they generally copy first time, every time without
BG> any problems?

KR> depends on the manufacturer, some are better than others, it also can
KR> very from piece to piece, but generally these days most are ok.

You can see how much I've had to do with EPROMs, can't you?  :)

BG> Also, can they be altered slightly, if required?

KR> if you mean can an eprom be changed, as you erase to all
"1"s you can
KR> change "1"s to "0"s but not vice versa. some
people leave an area of
KR> "1"s as a patch area, but its usually better to erase the
whole thing
KR> and start again. if you mean can the data be changed, then thats easy
KR> all the programming systems that i've used have edit capabilities, as
KR> long as you dont want to do inserts there is no problem.

I meant does the original image go to disk first, where it is then
editable, or is it copied directly into the new EPROM from the original? 
It may not matter either way, I was just covering all aspects of what may
be required.

Regards, Bill

--- Msgedsq/2 3.20