Hello! Sorry if this is the wrong newsgroup for this sort of thing. I have a jukebox thats about 25 years old (Rowe-Ami R-81). For now it works okay, but could use some playing with to clean up amp noise and such. But mostly I'm worried that someday the electronics on it will finally pop, and I'll have no way to replace them. I know the memory unit on it is some custom chip thats no fun to replace.
So, I got it into my head that it'd be interesting to see if I could replace all of the control electronics with something more modern. But, I'm a software guy. Programming the logic will be easy, but I dont know about controlling/reading the hardware. I should know enough about electronics that controlling some motors and stuff shouldnt be a huge deal, I hope. But I'm not sure about interfacing with the relatively large number of lines I have. Heres exactly what I'm working with:
User I/O Input 12 keyboard lines - (0-9, Reset) 5 coin switches (could ignore) Output 5 lights 10 display lines - (888 LED display: 3 lines to select digit, 7 for lights)
Operation Input 10 encoder lines (Encodes record magazine position) 1 tone arm cutoff switch 4 cam switches (Might not need to be read) 1 auto cancel switch Output 1 detent coil 1 record magazine motor 1 turntable motor 1 transfer motor 1 shift coil (right/left side selector) 1 amp mute relay
Diagnostics Input 1 manual cancel switch 1 scan switch 1 service switch
36 input lines, 21 output linesSo my question is, what sort of equipment would I need to do this? I'm thinking a PC based solution would be easiest for me since I'm a programmer. A microprocessor based solution might work okay too, but I'd still like to be able to interface it with a PC and I'm not sure how easy thatd be. But I dont know how I'd connect all the I/O lines. I dont know of any options for that many lines. A PC with a few extra parallel ports would be fairly easy, but they have mostly output lines so I'd need way too many. The microprocessor options I've found top out at around 40 I/O lines. Preferably less than $100 for the I/O interface, much more and I could buy a new jukebox. :) It doesnt even need to be fast, the fastest thing on there is the strobing LED display. I could probably do some clever things to reduce the number of lines, but I'm not sure. Like, maybe I could replace the 12 keyboard lines with the guts from a USB keypad if I go with a PC, reduce the encoder lines to 2 and track the record magazine position in software, or find a way that I wouldnt have to control the LEDs directly (serial connection to a small microcontroller?).
Once I can control/read the I/O lines, I dont think I'd have much trouble. Trickiest bit would be the relatively high voltage (28V AC/DC) required by some components, but I'm thinking that using a few relays would solve that. I hope.
Ah well, I hope this all made sense. Thanks for any suggestions. :) Joe