Mike Tyson's Punch-Out!! Password Guide For NES

Remember writing passwords down so you wouldn’t have to start the game all over again?

I do. Those old NES passwords could be a pain. You’d copy a row of numbers onto whatever paper was nearby, then hope you could still read it the next time you wanted to play. Lose the paper, mix up a digit, and there went your progress.

But the codes were interesting too. They weren’t always random numbers. Some of them had a system behind them, and I’ve spent plenty of time poking at that sort of thing. This time, I’m looking at Mike Tyson’s Punch-Out!!.

Doug Babcock already did the hard work of documenting this game’s password rules. I’m using his guide as the reference and building a generator around it. The goal here is simple: enter a record, get a password, and see whether it checks out in the game.

First, credit where it’s due

This project starts with Doug Babcock’s Mike Tyson’s Punch-Out!!: Password Guide. He laid out the three tables, explained the bit values and checksum, and listed several special passwords. That’s the reference I used while putting this generator together.

The JavaScript here is my implementation of the method described in his guide, not Doug’s original generator. I’m not going to dress this up as a brand-new discovery. I wanted to turn the documented rules into something people can use and test without doing all the arithmetic by hand.

What it does: It generates standard passwords from wins, losses, KOs, and circuit title. It doesn’t cover every unusual password the game might accept.

What’s going on inside the code?

The password is ten digits long, usually written as three digits, another three, then four. The digits represent parts of the record rather than one big number. In Doug’s explanation, each digit has three bits, and those bits tell us which values to add to a base code.

There are three versions of the table. You pick one based on the title and the number of losses:

Title	0 losses	1 loss	2 losses
Minor	Table I	Table II	Table III
Major	Table II	Table III	Table I
World	Table III	Table I	Table II

Wins and KOs use values of 80, 40, 20, 10, 8, 4, 2, and 1. The checksum uses 32, 16, 8, 4, 2, and 1. The script figures out which values make up the record, maps them to the right bits, and builds the ten digits from the table’s base code.

The checksum part

Here’s the rule from the guide: add the digits in the wins, losses, and KOs, then subtract the result from 63. That gives you the checksum value. It’s one more piece the password has to get right or the game may reject it.

That’s the short version. You can work through all ten rows with pencil and paper if you’re in the mood, but the whole point of the generator is to let the computer handle that part.

Have a go

Choose the wins, losses, KOs, and title, then click Generate Password. The input limits follow Doug’s guide: between 3 and 99 wins, no more than two losses, and KOs cannot exceed wins.

Your password

005 737 5423

Table I · Checksum 57

Minor title · 3 wins · 0 losses · 3 KOs

Some passwords to compare

I’ve put a few of Doug’s examples here so you can check the output. Click Load beside one of them and the form will fill in the record. The password shown by the generator should match the one in the table.

Record	KOs	Title	Guide password
3–0	3	Minor	`005 737 5423`
7–0	7	Major	`777 807 3454`
13–0	13	World	`267 853 7538`
65–2	51	World	`806 717 3070`
99–0	99	World	`940 861 8538`

Matching these examples is a useful first check. The next step is trying the password in the game. If one doesn’t work, please note the record and which version you’re playing.

Those special passwords

These four aren’t generated by the form above. Doug lists them separately in his guide, and they’re worth keeping around:

Purpose	Password	Extra instruction
Fight Mike Tyson	`007 373 5963`	Special fight-select password.
Another World Circuit	`135 792 4680`	After entering the final digit, press A, B, and Select together instead of Start.
Busy Signal	`800 422 2602`	Plays the game's busy-signal joke.
Credits	`106 113 0120`	After entering the final digit, press A, B, and Select together instead of Start.

There’s something satisfying about figuring out what an old password is actually doing instead of treating it like a magic code. This one becomes much less mysterious once you see the tables and checksum laid out.

The generator follows the standard method in Doug’s guide. It doesn’t claim to explain every password the game might accept, so there’s still room to test and compare results.

If you give it a try, tell me whether the passwords work on your cartridge or emulator. I’d be interested to hear what you find.

Reference(s) / Test Environment(s):

Doug Babcock, Mike Tyson's Punch-Out!!: Password Guide, version 1.02. The password rules.
https://gamefaqs.gamespot.com/nes/525246-mike-tysons-punch-out/faqs/37558
Passwords we're tested and working on Retro Games. Take note that Retro Games is not in any way affiliated with TNTTS.
Javascript tool by Erickson Deveza.