Adding TURBO MODE to the Tandy Model 100

A huge THANK YOU to PCBWay for sponsoring this video. Head over to pcbway.com and pick up the board for this mod for only $5.
I absolutely love my Tandy Model 100. But let's face it - it's a laptop from the early 80s, and it run as early-80s speeds. But fortunately, there's a new experimental mod that lets you run the Model 100 at a whopping 5MHz. It's not an easy one, though, because there are a lot of downstream impacts when you start messing with the system clock.
In this video, I'll take you through the process of installing the clock doubler mod, and I'm going to explain how it works along the way. We'll talk about some of the nuances of the Model 100, as well as intricacies of the timing architecture.
Links referenced in this video:
- 5MHz Upgrade Mod Wiki: bitchin100.com/wiki/index.php...
- PCBWay: www.pcbway.com
- 45ns EPROM Chip: www.mouser.com/ProductDetail/...
- ROM Adapter Board: bitchin100.com/wiki/index.php...
- ROM Images: bitchin100.com/wiki/index.php...

[@JJW410]

Ken, I was born in '95 and have never used any of these old computers but I've been binging all your videos! Keep it up, the production quality is great and your use of after effects to make technical details digestible is fantastic! :)

[@MCliffordAuthor]

I’m so here for this content

[@alexandermirdzveli3200]

Brilliant, as always!

[@Fezzler61]

Excellent! Enjoyed.

[@KrystianMajewski]

You know it gets good when Ken whips out the old TL86

[@abpccpba]

Thank You Ken.

[@vicenary]

That is a proper mod, that is. Not some FPGA replacement for the CPU, but something that has been thoroughly thought out and is understandable. If it's not quite working right you could drop a scope probe onto the board and work out what's happening, something you can never do with a BGA256 packaged FPGA. Also, love the "use the clipped-off leads" solution.

[@akiko009]

I suspect the game display doesn't work because it's already driving the LCD controller at close to its maximum bandwidth at 2.5MHz. Length of the bullet sound is obviously implemented as a countdown loop and at 5MHz it's half the length. The frequency of the sound is controlled by the same 8155 that runs the serial port, hence patching the timer in for the 8155 to make the serial port work right also makes sure sounds are still the correct frequency.

[@dondywondy]

Great video! But, after I install this, will my barcode reader still work?

[@bigbadhodad3894]

Interesting mod, more than Id want to do to mine, but cool none the less, I do wish someone made are REX chips though, that is a mod Id love to do, lol, I have a dial a rom but it doesn't include additional memory.

[@HSTVizle]

Wow