I thought I could learn Asm by disassembling single Axe Parser compiled commands,
but this idea was fail.   I read some tutorials and source codes, but there are still some issues:
1) How let I run my prog under 15Mhz processor speed?
2) How to randomize a word, like Axe Parser's rand^x?
3) I want to include Joe Wingbermuehles's fastcopy routine into my code, but I'm not sure what 'gbuf' has to be. I think it must be a constant pointed to the start of the Buffer, if yes, which adress is it on a TI84+? I dont use ion.inc, since this means to be unable to use ti83plus.inc at the same time.
Thats all for now. Thanks in advance!
Regards,
Aichi

1) Thank you!
2) Ok, I found a nice routine by Joe Wingbermuehle.
3) Perhaps gbuf is the same as the system pointer 'plotsscreen'.

4) http://wikiti.brandonw.net/index.php?title=Z80_Routines:Graphic:put8x8sprite I tried to copy the first routine into Mimas, but it seems like Mimas cannot handle the line LD  D, (IX) ôo. Does anyone know what the problem is?

Easier than calling SetExSpeed, you can set the speed yourself:
 in a, (2)
  add a, a  ; check if on a TI-83+ BE
  jr nc, is_a_ti83p
  ld a, 1
  out (20h), a
is_a_ti83p:

or use MichaelV's method, which works because port 20h is the same as 0 on the 83+ BE (so this also resets the link port):
 in a, (2)
  rlca
  and 1
  out (20h), a

But if you're writing an Ion/MirageOS program, you need to be sure to set the speed back to 6 MHz (write zero to port 20h) before exiting, since otherwise the shell and other programs won't work correctly.  In particular, depending on the shell, the ionFastCopy routine may not work correctly at 15 MHz.

Oh, and:

4) http://wikiti.brandonw.net/index.php?title=Z80_Routines:Graphic:put8x8sprite I tried to copy the first routine into Mimas, but it seems like Mimas cannot handle the line LD  D, (IX) ôo. Does anyone know what the problem is?

Yeah, that's a known issue with Mimas.  You have to write "LD D, (IX+0)" instead.

Well, bit 7 of port 2 is zero on an 83+ BE, whereas it's one on an SE or 84+.  So after the 'and', A is 0 on an 83+ BE, or 1 on a newer model.  As I said, port 20h on an 83+ BE is the same as port 0, so writing 0 to port 20h resets the link port.  Whereas on an SE, writing 1 to port 20h sets 15 MHz mode.

Yeah, that's a known issue with Mimas.  You have to write "LD D, (IX+0)" instead.

Ah, thanks. I should develope on PC while Mimas' early Alpha phase.

5) How compare I the HL register by using something like CP?

And here is the best one: (I think by calc84?)
or a
sbc hl, de
add hl, de

The flags are affected exactly the same way as cp.

And here is the best one: (I think by calc84?)

Code: [Select]

or a
sbc hl, de
add hl, de

The flags are affected exactly the same way as cp.

I debated posting that, but that addition will leave some flags (s, z, and n) with incorrect values.

Straight from the zilog manual for add hl, <register>:

Condition Bits Affected:
S is not affected
Z is not affected
H is set if carry out of bit 11; reset otherwise
P/V is not affected
N is reset
C is set if carry from bit 15; reset otherwise

To be honest, I actually forgot that S and Z were ignored. I bet somewhere in one of my programs I did that wrong.