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About dafa_123

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    Space Invader
  1. Ok, so I replaced the ROM and RAM with the ones from Console5, not luck, exact same symptoms. I am waiting for my replacement CPU and GPU. Hopefully, it will be one or the other... I'll update the thread once I have replaced them. Thanks everyone.
  2. I get the same "Booooouuuu" sound with or without a cartridge. The weird thing is I get different wave forms with and without a cartridge but the same "Booooouuu" noise... I have put the results of U20 without a cartridge, see pictures. If the ROM is the problem, how could I test it?
  3. I get the same results with or without a cartridge. Only a black screen with a constant "Booooouuuuu" sound. I don't see any reference on how to test U5 in the documentation that I have on hand. So I checked the voltage on U5 but I get different results every time I check. I checked with the oscilloscope and I get wave patterns on some pins, see pictures. I get the same results with or without a cartridge inserted. I am not sure how to properly test U5?
  4. I hope that I am using the trigger function correctly. I managed to get a wave form on U9:36 using the TVH function but I get a flat line on TVV. I am not sure if it's normal. I am unable to reproduce constantly the wave form using TVH. Sometimes, it's just a flat line. It could be an issue with my old oscilloscope since I often have to fiddle with the v/Div in order to see the wave form. I have ordered a new one online, but I probably won't get it for a couple of weeks. As for the sound, I only hear a constant "Boooooooooo" sound. No music and no sound effects. Thanks
  5. I do get a signal on 35 and 36 with the Frogger cartridge but 38 is still flat. The heat sink appears to be properly glued to U9.
  6. Can you upload all the pages from the manual? I would love to see the entire manual. Thanks.
  7. Thanks, I have the original manual with the oscilloscope. Here are some more tests. Nothing happens to U9:14 when I press reset.
  8. I think my oscilloscope might be problematic. I can't seem to get a good reading. I have attached a few pictures. I was thinking of getting the Hantek PC Based USB Digital Storage Oscilloscope 6082BE 80Mhz 2CH,EXT 250MS/s. I don't want to pay too much since this is a hobby. Picture 1: pin 20 1v/[email protected] Picture 2: pin 21 1v/[email protected] Picture 3: pin 25 1v/[email protected] Picture 4: pin 27 1v/[email protected]
  9. I ordered a TMPZ84C00AP-6 from China for 2.29$. Hopefully it will be compatible. If not, not a big lost. I am not sure if the fact that this one is rated to run at 6Mhz will cause any issues when run at 3.58Mhz. Thank you for all the help. I will update my post once I receive and replace the CPU.
  10. Ok, so I did some testing with my old oscilloscope. I can't test everything because the oscilloscope that I have, B&K Precision 1470, does not have the ns or sub 1uS/Div range. I started testing U1:6 I am able to see the main clock on U6 by using a 2v/Div and 1uS/Div. The wave is similar but smaller on my screen. I think that the main clock is Ok. I am unable to test U1:16 since I don't have the 0.2uS/Div on my oscilloscope. When I test U1:17, I get a flat line at ±3.5v U1:18 gets a flat line at ±4.5v U1:19 gets ±1v when the switch is off which is weird. Unable to test since it requires a 0.1uS/Div U1:20 gets a flat line at ±3.65v U1:22 gets a flat line at ±3.65v U1:24 gets a flat line at ±4.5v I stopped testing since, either the oscilloscope is malfunctioning, or the CPU is dead. Does anyone know if I can get a replacement CPU other than from another Colecovision? Is there a compatible CPU that I could use?
  11. Thank you for those documents. They will help me a lot. I do have a old oscilloscope. I will follow them and hopefully I will find the issue. I will work on it tomorrow and I will let you know if I find the issue.
  12. Hello, I have a Colecovision that was given to me that only display a black screen with or without a cartridge inserted. I have a limited knowledge of electronics but I did some testing and here is what I have so far: - I checked the PSU and I get the proper 5v, -5v and 12v. I also tried the PSU on another Coleco and it works. I even tried another working PSU just in case. - I connected the Atari Module and I get the image. I can probably rule out the RF module. - I checked the CPU at U1 and I get a clock signal on pin6 and I get 5v on pin 11. Not sure what else I can check here. - I checked the Bios U2, U3 to U9 and all chips get 5v. - I checked the VRAM U10 to U17 and they all get the 5v, 12v and -5v. - The cartridge slot also gets 5v. Not sure what else I can check or try. Any help would be appreciated. Thank you.
  13. Look here: https://archive.org/details/MAME_0.197_Software_List_ROMs_machines-bios-devices I found it here.
  14. Anyone have the ECS bios files required in MAME? ecs_rom.20 ecs_rom.70 ecs_rom.e0 Thanks.
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