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Middleway

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About Middleway

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  1. Disk space reporting is about as clear as mud 🙂. After doing some experiments with large files on my Windows 10 box, I think it comes down to how disk sizes are reported by HD/SD manufacturers, as well as how Windows handles them and reports them in Explorer. IMO the best way to do an apples to apples comparison is to look at the number of bytes. In Windows Explorer 1. For the file: Right click --> Properties and look at the Size where it shows the total bytes in parentheses. 2. For the SD: Right click --> Properties and look at the Free space in bytes I'm guessing the IMG file will be a little bit larger than the amount of free space on the SD. I don't think there's a problem with the file or the SD card.
  2. Here's a link to a barrel jack connector that I've used in different projects: https://www.aliexpress.com/item/32888655297.html?spm=a2g0s.8937460.0.0.44122e0eR821uc 5.5mm x 2.1mm is a common size for wall warts.
  3. MK4027N is the RAM type to search for.
  4. Hello, with weird video issues like this I would start with looking at the RAM chips. This seems to be a common failure mode in Channel F, I've seen bad RAM causing missing parts of the graphics, although I haven't seen the doubling problem you're having. With the RAM chips being socketed it's easy to experiment with removing 1 at a time (it will still show some sort of display with 1 of the chips out of the socket), swapping them around, etc and see how it changes. Good luck
  5. If you're in the U.S. and want to plug in a UK Wii PSU directly into a wall outlet (with a prong adapter) to power a Wii, I don't think it will work. From looking at pictures of Wii power supplies, it looks like they're not universal - they only work with the input voltage for the region they're made for. You would need a step-up converter to take the 110V from a wall outlet, step up to 220V, then plug the PSU into that. It would work then. Personal story -- Years ago I killed a network switch I brought with me to S. Korea by plugging it directly into their mains, not realizing it was not designed to handle 220V input. Doh! Luckily no smoke or fireworks... it just quit working. I have a better understanding now
  6. I have a second Channel F (Model 1) and successfully used 1 of its RAM chips to replace the defective one in the Model 2 and it worked. So looks like they are interchangeable. I had ordered a couple of MK4027N chips online but they didn't work, which complicated the troubleshooting. Still seems strange to me that the Model 2 is supplying +12V to Vcc and Vdd.
  7. I have a NTSC Fairchild Channel F with a graphics problem (see screenshot). It's a Model 1 with the hardwired controllers, internal speaker, etc. However the inside appears to be the VLSI version that I understand is what you would find in a Model 2. Through swapping around the RAM chips I believe I've narrowed down the issue to 1 bad RAM chip. I have some MK4027N-3 replacement RAM, however replacing the bad chip resulted in a black screen and the new chip getting very hot in a matter of seconds. As I started digging into it further I found a schematic of the SABA VideoPlay 2 which matches my motherboard (other than it is PAL vs NTSC). The RAM is labeled "330470" which also matches the label on mine. But it seems to be different RAM than the MK4027N-3. For example, the 330470 has -5v/+12v/+12v input voltage lines, while the MK4027N has -5v/+5v/+12v. The A0/A1/A2 address lines are different between them as well. When I measure the voltage on my RAM it matches up to the +5v/+12v/+12v on the SABA schematic. There is a reference on VESwiki to using MK4015N as replacement RAM for the VLSI version, but it has the same voltage inputs as the MK4027N. So it's left me scratching my head a little. It seems like there's a fundamental difference in the 330470 RAM type on the Model 2 board, but my Google fu has come up empty on confirming what type it is and if I should be able to replace it with MK4015N. Has anyone been able to successfully replace this RAM with some equivalent (other than a donor board)? Thanks!
  8. Thanks @goodtofufriday, I found your post on assemblergames a little while back and quickly bookmarked it, very helpful!
  9. I have a Channel F model 1 (hardwired controllers) and both controllers have the same problem as yours -- everything works except 'up'. I did some continuity troubleshooting and it appears the yellow wire is broken somewhere in the controller cable. The controller wires are very thin/fragile and seem to be prone to this. Still trying to figure out the best way to fix it with minimal cutting and patching.
  10. Found this Game Boy bundle at a yard sale for $15. Games are in great condition. The Game Boy needed some work -- had to clean battery contact corrosion, fix missing vertical lines, and general cleaning. Only remaining issue is a band of horizontal lines not working. I don't have the right tools to fix it so maybe sometime later. Having fun checking out the games on my GBA SP-101. I had almost no GB stuff before this find. I used to hit the yard sales more often but not so much the last couple of years. It was fun to find a little treasure like this and brought back some of the excitement.
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