1993 Called - can haz eeprom emulator? - Page 1
Forum section: electronics / general

author: BartManInNZ
author_rank: Contributor
timestamp: June 22, 2014, 11:31:30 pm
content: Rummaging around in my collection I came across the following - my first development board, hand-etched and soldered back in 1993/94 for my polytech course in Electronics and Computer Technology. At some stage I have removed the LM7805 and the eeprom will need replacing.We used to use an eeprom emulator for our development work - connected by parallel port to a PC and with a DIP28 socket on the board - you would simply 'print' your compiled .hex file and then power-on the device.The 80C552 uses the 8051 ISM - good old fashioned 8-bit at it's best O0, being a C64 fan I would have preferred a 6502 chipset but as they say "beggars (students) can't be choosers".Having spent 20+ years working in I.T. I am now in a position to return to my E.E. training and put this device and the more modern equivalents to some useful practical and money-making purposes. First-up will be building an eeprom emulator/burner so I can resurrect this board and make it work.

author: chickenHeadKnob
author_rank: Super Contributor
timestamp: June 23, 2014, 12:21:03 am
content: We must be using the same appellation for two different things. I don't see how that board could be ane(e)prom emulatoras it lacks the ribbon connector to parallel DIP pin plug I would expect. Doesn't the typical rom emulator replace a socketed rom with an offboard ram that can be written to? just curious

author: miguelvp
author_rank: Super Contributor
timestamp: June 23, 2014, 12:29:54 am
content: I think he is talking about an eeprom programmer.Edit: like this one:A long time ago I used to do that but with eproms, will have two and erase the one I was going to replace while programming the previous already blanked one with code produced from a cross compiler.I bet you can find USB based ones now, but I wouldn't know haven't done that for over 20 years

author: BartManInNZ
author_rank: Contributor
timestamp: June 23, 2014, 12:45:32 am
content: Quote from: chickenHeadKnob on June 23, 2014, 12:21:03 amIt's an 80C552 development board - I was simply stating that we used an eeprom emulator to do develop/debug our code for this particular board.

author: xwarp
author_rank: Frequent Contributor
timestamp: June 23, 2014, 12:58:23 am
content: If you ever decide to toss that board, I'd be very interested in catching it!I've been wanting a reasonably priced eprom emulator to save time on erasing eproms and having to rewrite them.With an eprom emulator, I could just patch it into my truck's ECM and make changes on the fly.

author: BartManInNZ
author_rank: Contributor
timestamp: June 23, 2014, 02:41:30 am
content: Quote from: xwarp on June 23, 2014, 12:58:23 amAs I said before - this is not an eprom emulator, I simply used an eprom emulator while developing code for this particular board.Like you I would like to acquire a reasonably priced eprom emulator a couple of links I have found thus far -http://users.tkk.fi/iisakkil/stuff.htmlhttp://esdn.com.au/Products/EEPROM_Emulator.htmlhttp://www.baltissen.org/newhtm/epromemu.htmhttp://www.worldofspectrum.org/z88forever/eprom-emulator/eprom-emulator.htmlhttp://www.sparetimegizmos.com/Hardware/EPROM_Emulator.htmhttp://www.esis.com.au/Programmers/Programmers001.htmhttps://www.futurlec.com/Programmers.shtmlJudging from the looks of the links above it may be that there is room in the market for an open-sourced eprom emulator?

author: chickenHeadKnob
author_rank: Super Contributor
timestamp: June 23, 2014, 02:49:50 am
content: Quote from: BartManInNZ on June 23, 2014, 12:45:32 amAh yes, instead of a windowed micro-controller, or now-a-days flash or one time programmable. I commented on a thread forum member terrahertz started that I didn't really "get" the nostalgia for old digital development equipment. I am of that era, now in my mid fifties and can see the value of restoring old analogue gear. Say power supplies or O'scopes, as I have always lusted for a tek 22xx, but the digital stuff - Meh. What we have now is so much better.Nothing wrong with doing it though, if that's what makes you happy. Horses for courses.

author: sleemanj
author_rank: Super Contributor
timestamp: June 23, 2014, 05:43:09 am
content: Quote from: BartManInNZ on June 22, 2014, 11:31:30 pmFor hand-etched that looks very tidy. How did you do the soldermask and silkscreen out of interest?

author: BartManInNZ
author_rank: Contributor
timestamp: June 23, 2014, 06:36:49 am
content: Dude... it was 1993 - a lot of isopropyl and MEK has been through my system since then... details are sketchy but from what I remember the board was drawn in an old DOS pcb program, somehow then transferred to PCB, etched with ferric chloride - modified silk screen printing press for the remainder.

author: BartManInNZ
author_rank: Contributor
timestamp: June 23, 2014, 10:48:42 pm
content: So from a cursory glance at my old documentation for the 80C552 board and the documentation for an Arduino Mega2560 it would appear that I could emulate an eeprom directly from PortL,A,C + a couple of additional lines for the control logic. The challenge will be programming the Mega2560 to include the compiled .hex file for the 80c552 - probably in a 2D array to allow for quick lookups, should be a challenge!

author: magetoo
author_rank: Frequent Contributor
timestamp: June 24, 2014, 03:58:45 pm
content: 1995 sayshello.I thought it was a pretty clever idea when I saw it (using counters and a shift register), and it needs only four data lines to the target.

author: jlmoon
author_rank: Unknown
timestamp: June 24, 2014, 07:32:15 pm
content: Quote from: BartManInNZ on June 23, 2014, 06:36:49 am1993 wasn't that long ago.. I can remember the eprom programming devices of 1983.. I still have my Modular Circuit Technology eprom programmer that will do 3 voltage 2708's, not hand etched though!..

author: BartManInNZ
author_rank: Contributor
timestamp: July 02, 2014, 03:08:05 am
content: Have started a 'hack' over on hackaday:http://hackaday.io/project/1595

author: rob77
author_rank: Super Contributor
timestamp: July 02, 2014, 03:46:32 am
content: are you sure it's for printer port ?i see a DB9 connector and a RS232 level shifter there