Pinouts: a guy on USENET traced some of the pinouts to:
A0-A7 at pins 1-8
D7-D0 at pins 9-16
A8-A14 at pins 33-39
There is no A15 pin ?
That could explain why I'm getting only 32Kb of data, instead of 64Kb...
But the ROM-chip has only got 28 pins...
Why are you mentionning pins 33-39 ?
This is interesting:
http://www.datamath.org/Forensics.htmhttp://www.rskey.org/~mwsebastian/miscprj/results.htm
arcsin (arccos (arctan (tan (cos (sin (9) ) ) ) ) )
8.999999007884 Toshiba T6M53 (TI-80)
8.999999007884 Toshiba T9838 (TI-60X)
8.999999007884 Toshiba TMP0620F (TI-67 Galaxy 1)
8.999999007884 Toshiba T9948A (TI-68)
So, it shares... calculation algorithms with these processors?
Very interesting, yes!!! Thank you very much!
Those all control 10-, 12-, 16- digit LCDs. T6M53A controls the LCD screen?
Yes that is very strange, I know. The TI-80 itself seems very strange.
But remember TI wanted to build a low-cost calculator.
So that could be understandable. "How does it controls the screen" is the question...
A note on DataMath: "Comments: The T6A43 and T6M53 are based on the Z80-ASSP family" which as you acknowledge is probably wrong.
I've allready talked on the TI-80 with Joerg.
After confirming it was not running a z80 core, he has modified some web pages, but as you can see not all of them.
Because it's mostly in french, with many hypothesis/errors. I've copied the facts here.
Who have you asked for information from? It looks like TI Cares and Toshiba (English) so far? Have you tried Toshiba (Japanese), Toshiba (Chinese), or Toshiba (Taiwanese)? It's possible they go to different people at different offices. I/We can help with this if you want.
I've asked:
- TI Cares (no reply yet)
- DataMath.org (Joerg Woerner)
- and 4 TI-z80 developpers: Brandon Wilson, GoPlat, Benjamin Moody (FloppusMaximus), Randy Crompton
- Toshiba (but they answered it was not the right office)
Yes, if you can help by contacting Toshiba, that would be great.
judge: could it be TLCS900-core? 16-bit, Toshiba, 1995, passing relationship with Z80 (backwards compat. w TLCS90, which is related to Z80 in a way)...
Joerg and I have allready thought to the TLCS-900.
I've received an email from GoPlat who has started analysing the ROM dump.
Here is what he has found out:
I located the TI-80's program/equation parser; it starts around address AF4E. It's somewhat similar to the parsers in the Z80 calcs, but unfortunately the bytes used to represent each token are different, so I can't always be sure of what I'm looking at. That said, here's what I've figured out about the TI-80's CPU so far.
An instruction either consists of a single 16-bit word, or two 16-bit words where the second is a jump/call target. A jump/call target word contains the address to go to divided by 2 (so the address is always even), with the highest bit being 0 for a jump or 1 for a call. Addresses range from 0000 to 3FFF (the part of the ROM we don't have) and from 8000 to FFFF (the part of the ROM we have).
Here are the instructions which I think I understand:
* 0040 = return from a call
* 1Cii = load some register (I'll call it "A" for now) with immediate value
* 74ii tttt = jump/call if A is equal to immediate value
* 76ii tttt = jump/call if A is not equal to immediate value
* 7Cii tttt = jump/call if A is less than immediate value
* 7Eii tttt = jump/call if A is not less than immediate value
* D200 tttt = unconditional jump/call
* F0ii = add immediate value to A
* F2ii tttt = add immediate value to A, then unconditionally jump/call
If he is right, then that doesn't match the TLCS-900 op codes...
If anybody wants the dump file, just PM me.