My favorite old pocket computer … drum roll!

…is the TI-66 Programmable Calculator.

TI-66 pocket computer and manual
TI-66 Calculator and Manual

It is small and light and Turing complete. The programming records key presses as well as allowing for entering instructions in an assembly-like language, so it is a great primer for learning full Assembly language programming, which is what I am doing now on my HP95LX.


I found this on eBay cheaper than they usually go for. I still need to make a data transfer cable for it, they are really expensive. Once I have the cable I can transfer drivers to the handheld so I can use Compact Flash cards for data transfer.

HP95LX and DOS Assembly Manual

As you can see from the picture, I am using to learn Assembly Language Programming under DOS. For now I am using the debug program to write small programs in Assembly, since I can’t put other software on the machine yet.