Can't figure out why checksum is invalid

[Crusa1der]

OSCR firmware version

2023 Version 13.1

OSCR hardware version

Select hardware version

Attach OSCR_LOG.txt file here

No response

System used

SNES/Super Famicom

Describe the issue.

Hey, I'm new to emulation in general and have been trying to get Super Metroid to work but keep getting the message of an invalid checksum.

Title: Superman Metroid Revision: 0 Type: LoROM FastROM IC's: ROM SAVE Rom size: 3MB (96 banks) Save Size: 8 KB Checksum: F8DF Press button...

Read ROM

Saving to SNES/ROM/Super Metroid/5/... [**] Checksum... 76F0 != F8DF Invalid Checksum CRC32...493C9489 -> Not found Press button...

It will then save a rom labeled Super Metroid.sfc as well as a text file of the same name and I've tried running it on both higan (which loads the game but doesn't output video or sound [shows fps and game title]), and Snes9x (which instantly tells me it's an invalid checksum). Any help would be appreciated. Also, I have not tried with any other cartridge, if that helps.

[PsychoFox11]

Do you get a consistent CRC32 on multiple dumps? I haven't checked this one and doubt a first party title would have an invalid checksum, but some games do - the console doesn't care. But the fact that it isn't running right in emulators tells me the dump is bad. Make sure it is clean as heck with some 99% alcohol and q-tips, till they are white. The OSCR is far pickier than real consoles about dirt. If you aren't getting a consistent CRC32 on each dump something is definitely not right with the connection (though in some cases even if it is consistent there could be a connection issue, but when it isn't, there definitely is).

[Crusa1der]

I cleaned the cart until there was no black or discoloration on the q-tip and tried again, got the same exact invalid checksum CRC32...493C9489 -> Not found Also, sorry for the late reply, didnt have any rubbing alcohol.

[PsychoFox11]

Are you sure it is a legit cart? Got a pic of the PCB? Even a bootleg with wrong CRC32 should load in an emulator though. Maybe with a checksum warning, but it would work.

I just noticed the "Superman Metroid" - something isn't right there

[Crusa1der]

![Uploading 20241024_170803.jpg…]()

[Crusa1der]

I just noticed the "Superman Metroid" - something isn't right there

No, it does say super metroid. My autocorrect was on.

[Ancyker]

Are you on the Discord?

[Crusa1der]

Are you on the Discord?

No, I don't really use those kinds of apps. Let me try to resend the photo

[PsychoFox11]

Other SNES games dump ok? Especially any with similar settings?

[Crusa1der]

Other SNES games dump ok? Especially any with similar settings?

I have not tried other snes or sfc games because I dont have others, but I can get another sometime next week or so.

[PsychoFox11]

Yeah you really need more than one to confirm if something with the dumper may be wrong. Ideally a few to test. Could be bad cart, bad OSCR, bad anything at this point.

[Barawer]

If you are using a computer port or something similar to power the OSCR try using a good wall usb charger. I've had issues like this due to not enough power.

[PsychoFox11]

Yeah I agree checking things like that, plus running the self check in the menu if you haven't, would be a good start - if other's don't dump well. Do carts for any console dump properly?

[Crusa1der]

I just got another game to try, sorry for the wait. Still invalid checksum, but it seems diffrent

[Crusa1der]

[Crusa1der]

I also cleaned the cart before trying so that can't be it.

[PsychoFox11]

I'd guess the problem is in your OSCR somewhere, rather than the cart. Does a cart for a different system dump? Unless the problem is on one or more pins that only SNES uses, it would typically affect other consoles.