So, the office is in what was a Learning Resources centre that included two TV studios and various editing rooms, so entirely possible its some kind of video processing kit.
So BNC was used for baseband which makes me think the serial ports are inputs to a video text system & the BNC is the output to a mixer. You have a VT100 attached to one serial port and the other is the feed. It's possible there's another board as well.
Any idea what “ACIA” might stand for? “ Analog Complex Interface Adapter”?
Also, the 1.8432-MHz crystal is interesting, since doubling this gives you 3.6864 MHz, which is very close to the NTSC color-subcarrier frequency (3.579545 MHz, which is about 107 kHz lower).
In any case, this is a very well-made wire-wrap board and it would be fascinating if it actually worked.
I would power up the board & connect a terminal to each serial port and see if you get a command prompt. Then connect to see if you get composite video out the BNC.
I assumed the crystal was for the clock. Some of those only think at 5Mhz or so & I seen to remember that frequency for 8bit systems. But maybe you're right. I'm trying to visualize what was in early video sections in systems requiring them.
Not anywhere near where Sun Microsystems was, though, right?
I mean, a friend and I made a 68K computer, wire-wrapped it, he did the hardware design, I wrote a cross-compiler 68K assembler in C for it (under MSDOS) and we came up with kinda the same thing. Just a lot more boards because it was spaced out further, and I had a pile of static RAM to lend to the cause.
It was a crap-load of fun. We taught wire-wrapping to my friend's girlfriend, and she could follow a schematic. IIRC, she did a lot of the memory bus. No mistakes. He still has it.
I recently found the assembler "bootstrap" I wrote that I thought I had lost. Sans headers:
Org Start_address ;Go to beginning of ROM. ; org $1000 Movel #Trace,Trace_vector ;Set trace vector. Movel #Buserr,Bus_error Movel #Adrerr,Addr_error Movel #Int_CTYr,CTY_intr ;Set CTY interrupt vector. Movel #Int_CTYt,CTY_intt ;Set CTY transmit int vector. Movel #Int_Tty0r,TTY0_intr ;TTY0, Movel #Int_Tty0t,TTY0_intt ; and TTY0 transmit... Movew #-1,TTY0r_chr ;Flag nothing in this.
On the back side it looks like the 5-Volt bus is connected, and I suspect the ground (“0 V”) bus is used as well. Perhaps it was used only for power and mechanical support.
I had to maintain traffic controllers on wirewrap backplanes & then later, phone co wire wrap terminals. At least the gauge of communications cables was large enough not the break from looking at it. PC board wrap is thinner than a multimode fiber.
Superb-Tea-3174@reddit
That was a lot of work. Wonder about its purpose.
jon-henderson-clark@reddit
likely a control. 2 serial ports & a BNC is what makes me say that. op, what was that old office doing back in its youth?
quentinnuk@reddit (OP)
So, the office is in what was a Learning Resources centre that included two TV studios and various editing rooms, so entirely possible its some kind of video processing kit.
jon-henderson-clark@reddit
So BNC was used for baseband which makes me think the serial ports are inputs to a video text system & the BNC is the output to a mixer. You have a VT100 attached to one serial port and the other is the feed. It's possible there's another board as well.
okapiFan85@reddit
Any idea what “ACIA” might stand for? “ Analog Complex Interface Adapter”?
Also, the 1.8432-MHz crystal is interesting, since doubling this gives you 3.6864 MHz, which is very close to the NTSC color-subcarrier frequency (3.579545 MHz, which is about 107 kHz lower).
In any case, this is a very well-made wire-wrap board and it would be fascinating if it actually worked.
quentinnuk@reddit (OP)
It would be PAL here as this is in UK.
jon-henderson-clark@reddit
I would power up the board & connect a terminal to each serial port and see if you get a command prompt. Then connect to see if you get composite video out the BNC.
I assumed the crystal was for the clock. Some of those only think at 5Mhz or so & I seen to remember that frequency for 8bit systems. But maybe you're right. I'm trying to visualize what was in early video sections in systems requiring them.
quentinnuk@reddit (OP)
68000 based wire wrap computer by the looks of it. Glad I didn’t have to build that.
50-50-bmg@reddit
IDK, being able to literally build a 16 bit computer from bare chips sounds like a great experience to have had!
msalerno1965@reddit
Not anywhere near where Sun Microsystems was, though, right?
I mean, a friend and I made a 68K computer, wire-wrapped it, he did the hardware design, I wrote a cross-compiler 68K assembler in C for it (under MSDOS) and we came up with kinda the same thing. Just a lot more boards because it was spaced out further, and I had a pile of static RAM to lend to the cause.
okapiFan85@reddit
Very impressive, my friend! It must have been quite challenging.
msalerno1965@reddit
It was a crap-load of fun. We taught wire-wrapping to my friend's girlfriend, and she could follow a schematic. IIRC, she did a lot of the memory bus. No mistakes. He still has it.
I recently found the assembler "bootstrap" I wrote that I thought I had lost. Sans headers:
Org Start_address ;Go to beginning of ROM.; org $1000Movel #Trace,Trace_vector ;Set trace vector.Movel #Buserr,Bus_errorMovel #Adrerr,Addr_errorMovel #Int_CTYr,CTY_intr ;Set CTY interrupt vector.Movel #Int_CTYt,CTY_intt ;Set CTY transmit int vector.Movel #Int_Tty0r,TTY0_intr ;TTY0,Movel #Int_Tty0t,TTY0_intt ; and TTY0 transmit...Movew #-1,TTY0r_chr ;Flag nothing in this.Movel #Stack_pointer,A7 ;Set stack pointer...Clrb Flags ;Clear the fucking flags!Andiw #$F8FF,SR ;Set priority to 0.Call RS232_init ;Initialize RS232 ports.batwings21@reddit
Is that s100 bus based as well?
WorldWideKerflooey@reddit
I don't see any of the connector pads wired up.
okapiFan85@reddit
On the back side it looks like the 5-Volt bus is connected, and I suspect the ground (“0 V”) bus is used as well. Perhaps it was used only for power and mechanical support.
Interesting-Ad1803@reddit
Sweet!
nixiebunny@reddit
Both a 68000 and a TI 340 processor.
WorldWideKerflooey@reddit
The TMS34061-12fnl is Video System Controller chip, circa 1988.
This could be a board built just to evaluate this chip.
The board has only an RS232 terminal connection and a video out.
jon-henderson-clark@reddit
I had to maintain traffic controllers on wirewrap backplanes & then later, phone co wire wrap terminals. At least the gauge of communications cables was large enough not the break from looking at it. PC board wrap is thinner than a multimode fiber.
Shamanjoe@reddit
Wire wrap always looks like a rat nest to me. A beautiful rat nest.
Sneftel@reddit
God that’s some neat work. It’s generally a bull** saying but here it’s true… They just don’t make ‘em like they used to.