redherring32 / opentendo Goto Github PK

Hello,

Can the 6116SA15TPG be replaced with the original Nes Ram ? It's very hard (and expensive) to find now ... I have sanyo lc3517bs-15 available on a damaged nes board.

Thanks in advance,

Hi,

This isn't an issue but I didn't have any other way to contact you.

Do you have a recommended place to print the PCB? I know there are several out there but looking for a recommendation (e.g. where you've printed it before) so it will be printed well.

Thanks,
Dustin

The component FC1 is missing it's symbol. Motherboard-rescue:Ferrite_Core-Schematic not found.

As well as DA1, DA2, DA3 and D4. "Schematic" library not found.

the line :
Note: At this point in time, any and all motherboards will require the use of an original CPU[1], and PPU[1] to function.

PPU[1] should be PPU[2]

I believe that was your intentions :)

(my first issue report ever on GitHub)

I have searched everywhere for a power/AV module either as a used one or a board that I can print myself, but it is completely impossible to find. There are some boards out there, but they are not complete or do not work without additional high def expansion cards.

Do you know about something that works with standard mono and composite? Or maybe you made something yourself?

Hi,

Trying to build a NES from scratch based on your board (thanks for putting that out there), and getting a pretty broken video signal on power on. I saw your comment on nesdev (https://forums.nesdev.com/viewtopic.php?f=9&t=21018&hilit=opentendo&start=15) that you were working on an updated BOM, and after digging into it some more I suspect part of my problem might be I've gone for the PAL UA6527P and UA6528P chips, and didn't realise I should adjust the clock to match.

If you're releasing a new BOM sometime, could be worth marking that X1 should match the PAL/NTSC choice? Unfortunately looks harder to find a 26.601712mhz clock so my PAL choice doesn't seem such a great move.

You've probably spotted it already, but I think there's a 20k resistor listed in the BOM for R8 when it should be a 12k too, from the board marking?

Thanks again, has been fun building it so far!

Hi,
in d530f00 you changed C20 from 51pF to 220pF in all schematics, but the pcb silk screen and bom still shows 51pF. I guess, this should be also changed to 220pF?

I accidentally broke the original 5 pin 6.8kx4 resister array from the original board, but I'm not finding this component anywhere over the internet.
There is any substitute of this component that I can use?

Hi, first of all thanks for all of your hard work! I'm using the footprint for the cartridge connector in a project, and when laying out the PCB, I noticed that the footprint for the cartridge connector seems to have one side reversed. According to the nesdev wiki page, pin 1 should be on the other side from pin 37 and pin 36 should be on the other side from pin 72. As it currently stands, the footprint is aligned such that pins 36 and 37 are directly on the opposite side from each other. Also, pin 38 seems to be labeled 28 (although this could just be an issue on my end).

I thought it might just be a difference in numbering, but the the CIC connections are supposed to be right across from each other, but on my PCB they are on opposite halves of the board.

It's entirely possible that I'm simply using the footprint wrong since I'm very new to Kicad, but if this is the case I can update the footprint with my fix.

On V1.1 The following are marked 'unused' R14, R16, C6 and C7, but not on V1.2

TC1, RA2, and R14 are also missing from the BOM.

C4, C6, C7, C21, and C44 are all 220pf. C21 is using a different wider footprint then the others. This can probably be consolidated.

On the schematic and the board C20, C43, and C45 are listed as 51pf. In the BOM though they are listed as 56pf (K560J15C0GF5TL2).

It might also make sense to mark these on the BOM somehow so people know they don't actually need to obtain them.

How exact does the frequency have to be for the PAL crystal?
Does it have to be exactly 26.601712MHz, or can it be slightly different?

Besides extracting the existing one out of one of the NES PAL consoles that I have (I have PAL Mattel NES consoles as I am in Australia), I can't find any place that actually sells that particular frequency.

Have looked at Digi-Key, Mouser, RS-Components, Element14, and eBay, and the closest I can come is 26MHz or 26.64MHz, with some varying numbers in the middle, but nothing bang on.

Well, except for AliExpress, where they come in lots of 10.

CY7C128A seems to be a cheaper alternative to the 6116SA15TPG $69SGD vs $5.54SGD for 10.
Looking at the datasheet they seem to be pin and voltage compatible.
Biggest difference I could see is that the CY7C128A is not rated for industrial and military grade ambient temperatures.
I don't expect any OpenTendos to be used on the wing of an airplane mid-flight, so it should be fine.

I wasn't able to boot up any game until I change R13. On the schematics and on the board silkscreen you mention 1.2k for R13.

On my original board I have 150k for R13.

I managed to boot it up with 150k.

https://github.com/Redherring32/UniversalPPU

I just finished the assembly of the Openendo board and I have a reset loop when turning on the console, it only happens with some games like Kirby Adventure or Tetris, but with Super Mario Bros / Duck Hunt and Famicom games (Rockman 3) using an adapter , they work right.
I currently have the CIC chip with Pins 4 and 13 disabled (in fact when I made the mod I cut both pins and it worked on the original board), will it be that I need a new CIC (like NullCIC or another of spare)?

Please make a BOM.

This looks like a fun project. If there was an easy BOM I would buy all the parts and give it a go.

I would even be fun to with an RGB mod.

Hi,
I would like to try this project but I don't have the software to convert the design into Gerber files. The last time the Gerber file was updated was 2 years ago. Can someone can take the last build from the master to create Gerber files RS-274-X version?

Thank you.

Not to distract from the Awesome work you've done with this board. I was curious if you have thought of doing this for the NES-101 and other JP variations of the board to allow for restoration of those as well.