Signs of a bad prg or chr

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ironsniper1
Posts: 27
Joined: Sat Jan 16, 2021 3:47 pm

Signs of a bad prg or chr

Post by ironsniper1 » Wed Jan 20, 2021 10:40 am

Hey everyone

I have a copy of excitebike that the chr chip would get really warm almost hot and the game would display nothing but a white screen, I cleaned the pins really good and checked for continuity between the different chips and the pins and they all tested fine,

So I desoldered the chr chip and downloaded a rom of the game and split it to fit on a 29C256 eprom and soldered it in, however I dont know what if any wires I need to solder or to where,

I also dont know if the prg chip is bad or not when I try to play the game I get this
https://cdn.discordapp.com/attachments/ ... image0.jpg

if anyone has any ideas on what I did wrong or what I missed please let me know

lidnariq
Posts: 10260
Joined: Sun Apr 13, 2008 11:12 am
Location: Seattle

Re: Signs of a bad prg or chr

Post by lidnariq » Wed Jan 20, 2021 11:53 am

That looks to me like your CHR ROM is fine, but something else is wrong.
Does the NES work fine with other games?
If so, it's probably the PRG that's damaged.

ironsniper1
Posts: 27
Joined: Sat Jan 16, 2021 3:47 pm

Re: Signs of a bad prg or chr

Post by ironsniper1 » Wed Jan 20, 2021 12:00 pm

lidnariq wrote:
Wed Jan 20, 2021 11:53 am
That looks to me like your CHR ROM is fine, but something else is wrong.
Does the NES work fine with other games?
If so, it's probably the PRG that's damaged.
yes all other games work fine no issues, i program a new prg and see, if it turns out the prg is bad would that mean the old chr chip might still be good?

lidnariq
Posts: 10260
Joined: Sun Apr 13, 2008 11:12 am
Location: Seattle

Re: Signs of a bad prg or chr

Post by lidnariq » Wed Jan 20, 2021 12:02 pm

Getting hot is a bad sign, but it's easy to only change one at a time.

For these old NROM games, you don't need to do any rewiring. See our article on our wiki: https://wiki.nesdev.com/w/index.php/Mask_ROM_pinout

ironsniper1
Posts: 27
Joined: Sat Jan 16, 2021 3:47 pm

Re: Signs of a bad prg or chr

Post by ironsniper1 » Wed Jan 20, 2021 12:07 pm

lidnariq wrote:
Wed Jan 20, 2021 12:02 pm
Getting hot is a bad sign, but it's easy to only change one at a time.

For these old NROM games, you don't need to do any rewiring. See our article on our wiki: https://wiki.nesdev.com/w/index.php/Mask_ROM_pinout
well i 'burned' a new prg and put it over the old chip and put it in my console and it started right up and i was able to play excitebike

https://cdn.discordapp.com/attachments/ ... image0.jpg

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