Mitchell Gant
Active member
dezbaz said:Hi Neil
Welcome to the forum
Yes a few of us are waiting on the solid state Laser player to arrive, the last part I need in my Dragon's lair is the disc. That will be a day in history when they arrive
Also I see you devised a SW and ESB switcher (Homemade). I would love to know more there.
Is it 2 boards (Separate SW and ESB) or did you write software?
Pics ??
I have a few SW and ESB boards I need to fix, and 1 working, so info like this can be valuable (IE how you did it)
I made this in the early '90's after I got an Empire conversion UR cabinet. I thought it would be cool to make it switchable from SW to ESB without having to move the machine and swap PCBs.
Bear in mind that the original PCBs in the cabinet I had was already an authentic Empire conversion, although I had another SW boardset as spare.
I had an EPROM burner and saw that I could use double-sized EPROMs with Star Wars code in the lower half and Empire in the upper half of each EPROM. Then I could make a wire link to the highest address pin of each EPROM and wire it to a pull up resistor to +5V, and then on to a switch to connect to 0V when I wanted to select Star Wars.
For the SLAPSTIC board I did the same but had to risk desoldering the EPROMs and re-soldering the new larger ones, as there was no height without hitting the sound board above it. This was the riskiest part for me.
For the AVG EPROM which was only a 2732, I decided to piggyback two chips and then just stick an inverter gate on the CE input, which I then used as the SW/ESB select line. Not sure now why I did it this way rather than the simpler way of using a 2764 28 pin EPROM.
The high score/settings NOVRAM I didn't know how to deal with, so it just trashed the score /settings data each time it was switched.
It was a crude, brute force way of making it switchable. I also found out that the mathbox PROMs were changed for ESB. The ESB ones would happily let you play SW, but trying to play ESB with the SW mathbox PROMs led to just the AT-AT walkers legs being visible, with no body I seem to remember!
