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It can be emulated with a netlist (discrete sound) if all components/values are known.
sean: Do you know the R/C values for Big Trak? The schematics online say R=83K, C=100pf, which would imply around 125kHz. But comparing it to YouTube vids, it should be around 200kHz.
The Coleco Football game is also too slow with R=39K, C=100pf. If I had to guess, I'd pick R=30K... orange-black-orange instead of orange-white-orange, hmmmm big difference in contrast.
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My Big Trak has an 82K resistor (Gray Red Orange) and a 100pF cap (Brown Black Brown). H2H Football has an 39K resistor (Orange White Orange) and a 100 pF cap (101J). I measured the Big Trak resistor in circuit at 83.8K and the H2H Football resistor out of circuit at 39.3K. My meter won't go as low as 100pF to check the caps. Before I pulled the chips, I measured 195Hz between pins 1 and 4 of H2H Football, and 588 Hz between pins 26 and 4 of Big Trak. Those are both E revision dies; you think that has anything to do with it? Remember when I hooked up some TMS1100s to the Entex Baseball 3 cap and resistor to measure its frequency? Es were faster than Bs. Measuring the frequency slowed it way down, but it's possible that the ratio of B speed to E speed is correct. That would make Es 11-12% faster. Ok, Entex Baseball 3 is working in MESS. I'll update the notes if you worked out how to measure its osc freq. I connected the cap and resistors from BB3 to 4 other TMS1100s - two were B-revision dies and two were E-revision. Interestingly, the Es are faster than the Bs- B amateur = 169K, B pro = 218K, E amateur = 188K, E pro = 244K. The original chip was a B, so I guess 169K/218K is the way to go.
Last edited by seanriddle; 04/26/15 03:11 AM.
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I got a Tactix game; it's a 1980 Simon/Merlin-type game from Castle Toy Company. The CPU is a NEC D557L, which is listed in the 1980 and 1984 NEC Catalogs. The 1980 book says it's in the uCOM-43 family, but the 1984 book says uCOM-4. Both catalogs say it has 2000 bytes of ROM, not 2048, although other chips are shown having 2048. It has a test pin that the data sheet says "connect to VSS", so I'll see what happens when it's connected to VDD.
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It is really 2048; the databooks claim the upd553 is some non-power-of-2 ROM size, but it really is power of 2. Kevtris has a rig set up for dumping upd552 and 553 (and upd650), IIRC it involves selective insert of NOPs and 'jump following' to dump the entire ROM, it isn't straightforward.
The Hitachi MCUs on the other hand have a built in test ROM which can be used to bank in any page arbitrarily and are somewhat more straightforward to dump, if I remember right.
LN
"When life gives you zombies... *CHA-CHIK!* ...you make zombie-ade!"
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the 557 appears to be a 28 pin version of the 553, so it's probably the same die in the package. I should be able to dump it with my existing rig if I add a socket for it.
And yes, it's really 2048 bytes and not 2000. I don't know why the idiots kept saying 2000 in the data books and data sheets, when it clearly is 2048 on all the dumps I made. The programming manual I saw even re-enforces this lie by saying ROM can only be at 0000-07CF. This is not true at all.
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Here's another one. Bandai Machine Man. The broken filaments can be seen on the pictures. Segments A, B, and F of the 7-seg area is all connected internally via some kind of leakage path but if I pulled down the other inputs I could determine where things connected. http://blog.kevtris.org/blogfiles/Handhelds/Bandai%20Machine%20Man/
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I was amazed the VFD still partially works with that kind of damage, especially with the segments partly shorted together by the broken filament debris.
LN
"When life gives you zombies... *CHA-CHIK!* ...you make zombie-ade!"
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I thought maybe 48 bytes of ROM were inaccessible for some reason, like the 3870/42, which loses the top 64 bytes of ROM for RAM.
I spent a couple of hours playing with it. I was hopeful it was one of those that just spews out ROM contents in test mode. When the test pin's at VSS, the game plays normally. At VDD, nothing happens; all the output pins are low. Floating, it looks like it's executing random instructions. The chip has 1 4-bit input port and 2 4-bit I/O ports, so I tied all those low with 1K resistors to see if the chip was using those inputs as the address, but that didn't change anything.
Can I send you the chip (and maybe a couple of Rockwell's that are hassling me, too)? I'd like to get them back after you dump them so I can torch them and map out the bits.
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I thought maybe 48 bytes of ROM were inaccessible for some reason, like the 3870/42, which loses the top 64 bytes of ROM for RAM.
I spent a couple of hours playing with it. I was hopeful it was one of those that just spews out ROM contents in test mode. When the test pin's at VSS, the game plays normally. At VDD, nothing happens; all the output pins are low. Floating, it looks like it's executing random instructions. The chip has 1 4-bit input port and 2 4-bit I/O ports, so I tied all those low with 1K resistors to see if the chip was using those inputs as the address, but that didn't change anything.
Can I send you the chip (and maybe a couple of Rockwell's that are hassling me, too)? I'd like to get them back after you dump them so I can torch them and map out the bits. Sure I can dump them. To get the data out, it's a bit more nuanced. 2 of the pins (near the corner.. 39 and 40 I think) control things. One lets it force NOPs and the other lets you execute a jump. So you have to do a bunch of code that counts clocks after dumping the first bank on reset. Then you count clocks up to each jump/call and then let it execute it get into the new bank. Then you have to keep following jumps/calls to get to all banks. The HD388xx is like that only worse.
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Those are both E revision dies; you think that has anything to do with it? Remember when I hooked up some TMS1100s to the Entex Baseball 3 cap and resistor to measure its frequency? Es were faster than Bs. Measuring the frequency slowed it way down, but it's possible that the ratio of B speed to E speed is correct. That would make Es 11-12% faster. Ah! Yes, that must be why. The game with the NEC MCU: Can you make a pinout before you send it off to kevtris? Then we can emulate it when it's dumped. It will fit right into this driver: http://git.redump.net/mame/tree/src/mess/drivers/hh_ucom4.c
Last edited by hap; 04/26/15 10:08 AM.
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