Hey, it's Katherine.

I have discovered many unique things with Bop It in the almost 18 years I've been into it. But one of the most fascinating things to me that I've discovered is called a Test Mode.

A Test Mode is a manufacturing technique that allows you to hold a combination of actions on the Bop It, and either take a battery out and reinsert it, or press the RESET button if it has one, and then it can do a number of things, almost like a debug or a diagnostic mode.

From there, you can test the actions, the speaker (projected with a high frequency sine wave), microphone, accelerometer, lights, whatever else. And it will even allow you to hear every sound programmed into the microcontroller in the main circuit board. It plays every voice clip, every beat of the game, and the newer ones from 2020 to now do every single number from 1 to 100.

As well as testing all of these things, there is one thing in the Test Mode that I log in my archive and on my website, and that's what's called a Revision Number. It's basically the programming version number, and some Bop It units will have several revisions with different Revision Numbers because they fixed the speaker quality, or they fixed something in the sound Test Mode, or adjusted the programming of the way it's played. Think of it as kind of like your iPhone. You have your iPhone's iOS version and when you do a software update, it will change to either a 'X.1 or a 'X.0.1' or whatever it may be. Well, with a Bop It, Hasbro and manufacturers can't connect the Bop It to the internet to perform a software update to a new version, so Hasbro releases a second unit with the new revision.

I've logged over 200 Revision Numbers on my website, and I have them color-coded between confirmed, not confirmed, international confirmed, international not confirmed, and also some internal test numbers I found once when researching. And yes, international versions of Bop It, even if they're the same Bop It unit, they'll have different Revision Numbers.

Revision Number formats have changed a lot over the last 30 years that Bop It has been around. They went from just a number, to putting 'Score' before the number, and in the current era, they have the Retail SKU number, the region, and then the number. The last format of Bop It that I mentioned here has a computerized female voice reporting the Revision Number, and I could not find any information about the voice whatsoever online, and as she has been reporting in the Bop Its since 2021, I decided to give her a name earlier this year on my YouTube channel. Her name is GWEN. GWEN is an acronym that stands for 'Girl Who Enunciates Numbers'. It's been a canon piece of lore on my channel since March 2026.

Now, I will mention that some Bop It versions may not have a Revision Number at all (the 2002 release in the main lineup doesn't), and there's one from this year that doesn't even have a Test Mode, as it was made by another company though licensed by Hasbro.

Test Modes and Revision Numbers have definitely been some of the most interesting pieces of Bop It in my archiving. But the last thing I'll mention is something I actually found on accident earlier this year.

In the Bop It! Bounce (2010), if you go into a segment of the Test Mode, and you mess around with the two buttons a bit, it will announce a huge number: 268,435,455. And I thought, that can't be the cap total for the game to score up to. Well, then I got out of Test Mode, and that number did transfer over to my 'Total Hits' which was an accumulative game lifetime total. I played it and attempted to add a few more points to the total. After turning the game off and then back on again, it still said the same number: 268,435,455 Total Hits. I thought, what is going on here? And then, it hit me...

Bop It programming is made of code, and technical code like this is typically binary, right? Bingo. I looked to see if 268,435,455 was a number in binary where all the switches were on (all 1s), and... it was. 268,435,455 is 2²⁸ - 1 (since 0 counts as a number in this; from 0 to 268,435,455 meaning there's 268,435,456 numbers), which in binary is 28 consecutive 1s, and that's why it wouldn't budge past 268,435,455: because one more than that could break the code and crash the game. Programming has its limits.

All in all, Revision Numbers and Test Modes and the many hidden secrets in programming are by far one of my favorite things to uncover when it comes to Bop It archiving. I've looked through the circuit boards before when taking Bop It units apart sometimes, and I recognize a lot of the stuff in there too, since I used to play with a circuit making set when I was a teenager. But as for everyone else on my YouTube channel, it's more fun to do the Test Mode, find out the Revision Number (especially with new releases of Bop It), and then play all the sounds in the game.

I did my first Bop It Test Mode on video on September 7, 2016. I didn't have a YouTube channel yet when I made that, but I am celebrating 10 Years Of Test Modes with a video tonight to celebrate my first Test Mode.