5 Aug
2007
5 Aug
'07
3:23 a.m.
Tony Duell said:
IMHO, more important than the EPROM programmer is an
EPROM emulator. This
is a box of RAM that connectes to the EPROM socket of the target system
(the board you'be just made) and also to a host machine (PC, parallel
port, serial port, USB?). YOu can quickly download perogams into the
emulator, which then appears exactly as the EPROM does ot the target, and
the latter can therefroe run said programs.
The advantage over using EPROMs is that you can re-write the RAM as many
times as you like (EPROMS have a limited number of program cycles) and
rewrite it quickly. Unless your programming is a lot better than mine,
you will go mad if you have to wait 20 minutes for an EPROM to be erased
and reprogammed. each time you want to make a change!
I haven't so far reached the maximum # of programming cycles for EPROMs in
any experiment. *) As I recommended you might use EEPROMs instead of
EPROMs mainly because of their moderate capacity (you won't need PC FLASH
ROMs with 1MB or more for an 8 bit system) and because they don't need
erasing in the UV coffin.
*) Maybe your and my programming strategy differs; now with SW emulators
for almost any old CPU being available ona PC, I tend to test my code in
an emulator, often with single stepping first before I make a HEX file to
burn it; even with EEPROMs - the old turnaround cycle of change a byte,
program, insert and test how far it works is still too long even with RAM
boxes. Admittedly, in the old times, without PC emulation, I did a lot of
paper testing work first before burning the stuff into an EPROM; this
discipline meanwhile degraded...
--
Holger