Data I/O 29a Remote Mode

 Technical Info  Comments Off on Data I/O 29a Remote Mode
May 162016

Now that I had the Data I/O 29a in a working state I attempted to see if I could get it to communicate with a PC using the Promlink programming software. Unfortunately I fell at the first hurdle as my unit did not have a remote mode available. This can usually be accessed by using the command, “Select”, “F”, then “1” then “Start”, and “Start” again. On my unit this command was not even valid! Interestingly the manual does state that remote mode is “only in models equipped with this option”.

I then noticed that my device had a rom set labelled “324-0029”, whilst my friends unit, which could go into remote mode, had a rom set labelled “324-1024”. Both prom sets were exactly the same and these were labelled “324-1980 Rev A”. So I decided I would copy the 324-1024 roms and try them in my system. Luckily several collectors had some of these roms spare they could post to me (TMS2716’s) and I was pleased to see that once they were burnt, my unit now had the ability to go into remote mode aswell.

Next step was to build the serial port lead to make the connection. This required a 25 pin Dsub male connector and a 9 pin DB9 female connector. I found details of the pins used and connection settings at the following page

Once the lead was made I then had to find copies of the software. After a bit of searching I found a FTP site that had what I needed. The link for the site was

This site had various versions of the programs. Most notably 341-1991, and 61. What I discovered is that the unipak works best with 341-1991, and unipak2 or unipak2b works best with 61.

The site also had txt file lists of all the roms, and proms it could burn on each pak, so that was incredibly useful information.

I installed the software on an old laptop running Windows 95, and on my first attempt I was greeted with the message of “contact with programmer established”.

I wanted to try and get the unit running on a Windows 7 PC, soley for the reason that I didn’t want to use multiple PC’s or laptops to run all of my test equipment. I downloaded the software DOSbox and installed it on my Windows 7 box. The trick to get this working is to make sure that the serial configuration in the dosbox.conf file is configured correctly. I used the settings:

serial1=directserial realport:com1 irq:4 bytesize:8 stopbit:1 parity:E

Once that was configured I copied the promlink software to the root of my C:\ drive and launched DOSBox. Once the folder was mounted using mount c c:\promlink I was able to launch the Promlink software and establish a connection.

I’ve dumped both rom sets and prom set, and made them available below. If someone else comes across the same issues with remote mode it should be fairly easy to sort out with these files, as I could not find copies anywhere else:

324-1980 Rev A Proms (11 downloads)
324-0029 Roms (14 downloads)
324-1024 Roms (12 downloads)

Vs. Castlevania / Top Gun PCB

 Nintendo Vs  Comments Off on Vs. Castlevania / Top Gun PCB
May 012016

Myself and a fellow arcade collector have started working on a reproduction daughterboard for the Nintendo Vs. system which will allow Vs. Castlevania or Vs. Top Gun to run on a dual (Red Tent) or single standalone system.

These daughterboards are very hard to find and can be quite expenisve to buy, so we believe this is a good alternative. We are also looking at the possibility of making another board for Vs. Dr.Mario, but this has some additional complexities we need to work through.

This is the circuit diagram my partner on this project has produced:

Data I/O 29a Repair

 My Projects  Comments Off on Data I/O 29a Repair
May 012016

I spotted an untested Data I/O 29a programmer with Unipack on eBay a couple of weeks ago, and took a gamble and bought it.

When I received the unit I plugged it in and it powered up, but nothing was displayed on screen. The unit is meant to say “Self Test Ok” if it is working as expected, so clearly something was wrong.

I started taking the device apart, and it was fairly clear that it had been opened before as various screws were missing. The good thing about the unit is that it is fairly modular, and most chips are socketed, so I began testing each chip. I found that my ABI chipmaster failed both the 6802 CPU and 8279c keyboard controller, but passed everything else.

So I bought some replacements for both chips, hoping this would fix the issues.

Whilst I was waiting for the replacement chips to arrive, a local collector lent me his working Data I/O 29a. Although this unit had a different memory expansion board and rom set, I was able to check the Unipack, and my own rom/prom set, as well as keyboard display and that was all working ok.

Unfortunately the roms are TMS2716’s so a different pinout to standard 2716 eproms, and I had nothing to read them with to verify them or save the data from them.

The new parts arrived yesterday, and I put the unit back together with the new chips in place. I then powered on the unit and was pleased to see the message on the display say “Self Test OK”.

The next challenge is to make a serial cable for the device and see if I can get it communicate with PromLink on a PC.