I went on ebay and I bought two of these as spares or repairs. There should be a reasonable picture of one with a "Switched Fault Unit" as an attachment. After some work they both operate. Well, they run code from rom and display memory contents etc. I have yet to fully test them. They had been badly stored and scavenged for parts.

I found a scanned "User Manual" at http://www.ee.siue.edu/~smuren/ece282/l ... manual.pdf .

It refers to the "Technical Manual" and "Experiment manual" which I have been unable to find. If anyone knows of the whereabouts of these I would be most grateful.

It has been many years since I last did any 6502 programming and would like to know what editors, assemblers and simulators you would recommend. I last used dos based sim and assemblers on old 80186 machines.

I'll also need to sort out the programming method for these. It has a built in cassette audio I/O for program save and load. I could use a line in on the PC for saving and loading. I used to use an eprom emulator device many years ago. Writing and erasing UV Eprom is a painful process when coding. I know, because a lecturer made us firstly type in the code on the trainer board for months then use eproms for months. Eventually he walked in one day with the emulator and smiled. At least it made us take care when programming but it still hurts to recall the pain of the process.

Anyway, many thanks in advance for any help.

John

You should find something you like in the links at http://wilsonminesco.com/links.html, about the middle of the page, the last 10 lines above the heading, "for individual computer brands:" It seems like everyone does it differently though. I use the C32 assembler listed there. I have never found simulators to be of any real use after I truly knew the instruction set.


More common would be to have a monitor program in ROM, and use it to operate a serial port to download your last assembly into RAM. I did something similar to that 20+ years ago, and periodically collected all the new working portions of code and added them to the ROM.


When I was doing EPROMs a lot, I kept a set of them cycling, and kept the UV eraser going most of the time. When I was ready to do a new EPROM, I'd remove from the eraser the one that had been there longest, and put the last-used one in. My Needham's programmer (darn-- Needham's is out of business now), using the quick-pulse algorithm, programmed an EPROM almost as fast as you could put it in the ZIF socket, press the key, and remove the EPROM. Then of course I'd put it in the ZIF on my project. At a few minutes per cycle, it definitely was not like the instant turn-around I get with my Forth system where I can modify the program while it's actually running, but not bad for EPROMs.

Some relevant sections of the 6502 primer are: (This material won't all be new to you, but there's probably something helpful)
17. General Steps For A Successful Project
18. Program-Writing: Where Do I Start?
19. Debugging
20. Tips For Programming the 65(c)02 (sometimes affecting hardware design optimization)

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Hello GARTHWILSON

Thanks for the reply. The links you provided have yielded many useful articles and programs.


Re: Monitor Rom

Upon receiving the boards I unboxed the first to find it scavenged for parts. My heart sank badly when I noticed the Monitor Rom was missing. I franticly unboxed the second. To my great relief it was there. There were less parts missing and it wasn't so battered.

My first action was to remove the rom and read it. Upon a successful read and verify I copied it to a blank spare 2716 I had. That was close. I couldn't care if all the other parts were missing as long as I had one good rom.

Repopulating the board, repairing the damage and using some contact cleaner in the oxidised sockets brought them back to life.


So, now I'm on to using them.


Many thanks again

I had to just say 'awesome' and 'good luck', looks like some great progress.

_________________
65Org16:https://github.com/ElEctric-EyE/verilog-6502

I have been looking into the monitor rom from the Emma 2. It has a contiguous gap of 330 bytes that is address decoded. I was hoping to find some space in there for some of my own routines but I wasn't expecting that much.

So far these routines have been mentioned in the manual.

Data Insert Routine
Display 8
Display routine
Multiply by 10
Multiply by 16
Hex2Dec/Dec2Hex
Branch Offset Calculator
Re-locator
Checksum Routine
Write 4 Characters to display
Display Memory Contents
Display Memory Contents of indirect address
Display Accumulator Contents.
Display 4 Characters
Read the Keys
Output Data to the Cassette interface
Input Data from the Cassette interface


I have found them in the rom using a hex editor. I have also manipulated the rom image to correctly reflect the address decoding of the sections. This I have run in an emulator and it seems to run the monitor program without halting. I have only given it a cursory inspection but I'm happy I have correctly organised the code space.

If anyone has any suggestions as to what I can put in the available space I would welcome them.


Cheers

Just a thought, maybe some code in that space to program a few bits in the VIA port for communicating with i2C EEPROM or other devices.

It's good that you have a user EPROM socket as well.

Have fun with your new project!

That's an excellent idea and I highly recommend it. The 6502 primer's circuit potpourri page has info on it with a sample circuit with explanation and a link to working accompanying code, at http://wilsonminesco.com/6502primer/pot ... ITBANG_I2C. There's a brief comparison of synchronous-serial interfaces at viewtopic.php?t=1301&start=28, with a set of links at the end of the post.

_________________
http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?

Hello clockpulse and GARTHWILSON

Thanks for the replies.

This was exactly the stuff I was after. Some useful frequently called routines that would save loads of space inside my programs. The links were awesome. I have loads of ICs kicking around my house. I was about to sort out the interfacing of some dual output DACs. In the links were some important safety tips just for this task, nice. The I2C looks like a winner as well.

I will take my time to check the links more thoroughly in the coming days.

Many thanks again

Hi 68k-dude,

I have a fair number of these boards at home, with a colection of the manuals. I remember the switch fault board as it was used a long time ago when I was taught digital fault finding.

Can't get to the manuals at present as I am currently working in Germany, home is in Bristol UK.

Amazing, and good luck.

I'm curious: The manual goes on about the 6522, and that's what you can experiment with (top left), but the chip they used for the keyboard is a 6821. I think that would have been my first question as a student -- why not at least use the 6521?

Well back in Bristol again.

I have the following EMMA manuals.

EMMA II Technical manual
'EMMA@ Hardware Manual
'MAC' Microprocessor Application Card
'EMMA' Experiment Manual
Peripheral Hardware Manual
EPROM Programmer/RAM Expansion Unit and Switched Fault Unit
Demonstration Programs for EMMA II (EPROM SE188)
Two practical sheets - Using the Timers and Digital Plotting table.

Can scan to PDF if needed.

The 65xx equivilant to the 6821 was actually the 6520. This was a rare beast by the early 80s although 6522s were very popular. The 6821 could be connected directly to the 6502 bus and it was somewhat cheeper then the 6522. This lower cost was probably the reason for using a 6821 instead of a second 6522.

_________________
Shift to the left,
Shift to the right,
Mask in, Mask Out,
BYTE! BYTE! BYTE!

The first version of the EMMA board used a 8154 for the keyboard/display interface.

I've got an original Emma (eBay again) and I'd be interested in some of those scans. I could only find the Emma 2 manual at the time. I have however figured out the connectors and the address decoding from looking at the board and disassembled bits of the ROM.

It has been a while since making the original post.

Firstly. Many apologies to cheekyfox. Sorry for not contacting you or acknowledging your post. I offer this bitter explanation as to my absence.

My current employer has this year repeatedly left on extended holidays to Russia. When I say extended I mean two months at a time then back for a few weeks then two months away again then repeat. The extra work load of having to run his company for him while he is away has meant that my spare time has been greatly reduced. Also, as my job is as an electronics engineer the last thing I want to do after a bad month or two is electronics. I write this post safe in the knowledge that I have written my resignation letter and no longer care for my current employment. I will be taking up a position at my local university on a reduced wage but also a much reduced work load. So, now I look forward to carrying on with my enjoyment of life and helping to educate others. With all that said I would like to thank everyone that has posted in this thread.

Now on to where I left off. (continues as if nothing had happened)

Hello cheekyfox

Many thanks for your kind offer to scan some of your fine documentation. For starters I am very interested the "Technical Manual" and "Experiment Manual". I may in future also need some of the others. If you could scan them I would be most grateful. As an option and to save you the time involved, I could pay a large deposit if you would you be willing to post the documents. I could then read them and scan those that I feel I would need in the future then return them via Royal Mail Special Delivery.

Many thanks

John