Tutorial 2
Key Differences - TI-83 vs. TI-83 Plus vs. Z80 Asm

Overview (Part 1)

In this tutorial, you should learn the key differences between programming for the TI-83 and TI-83 Plus and the Z80 CPU.

Compare and Contrast

Over all, programming in Asm for both calculators is not all that different. In fact, most TI-83 Asm Programs will work on the TI-83 Plus, and vice versa (With some porting of course). The TI-83 Plus was designed with applications in mind. So to utilize that function, some changes in it's Asm programming were made. You should know what the differences are when programming the TI-83 Plus in Asm after reading this tutorial.

The TI-83 Plus uses the B_Call() macro for ROM calls instead of the regular call macro.

Asm programs (Not Applications) written in Asm are limited to 8K in size.

Most (Some) TI-83 Asm programs will run on the TI-83 Plus provided that a few minor changes be done. They require that the original source code be re-assembled for the specific memory addresses for the TI-83 Plus.

ex. TI-83 ROM call: ex. TI-83 ROM call address: call _clrLCDFull _clrLCDFull =4755h ex. TI-83 Plus ROM call: ex. TI-83 Plus ROM call address: B_CALL(_clrlcdfull) _clrlcdfull =4540h

Conclusion (Part 1)

TI-83 Plus programs only need to slightly changed to run on the TI-83, and vice versa. But since the TI-83 Plus has more SafeRAM areas, TI-83 Plus programs using these SafeRAM areas may not be run on a TI-83.

Overview (Part 2)

There are differences between programming in Asm for the TI-83/+ and Z80. They are explained here.

Compare and Contrast

First off, the ROM calls used in TI-83/+ are unique only to the TI. That's because the ROM calls were developed by TI (not Zilog) for use with only the TI-83/+ calculator and stored in the TI's memory. So don't use these ROM calls on the a lone Z80 (it's OK to use them on the TI-83/+ Z80). Z80 instructions however, are compatible between the two because the instructions can be used on all Z80 CPU's.

Conclusion (Part 2)

That's about it between Z80 Asm and TI-83/+ Asm. Just the ROM calls. Now that you know these differences, you can gather the right information for each and incorporate them into your own programs. You can also look in the Z80 Instructional References section for more information.

Tutorial 3