Your forgetting to set the interupt mask would be my guess
try tacking this before you restore progptr
Xor a
out (3),a
ld a,%00001011 ; this set interupts to go on with hardware timer 1 the on key and the link port
out (3),a

more info on port 3 is here
http://wikiti.brandonw.net/index.php?title=83Plus:Ports:03

hopefully that helps ^_^

Edit:

you may also want to look at port four bits 1 and 2
http://wikiti.brandonw.net/index.php?title=83Plus:Ports:04

used for setting the speed of the hardware timers ^^

Along with Geekboy's suggestion. You also need to reenable interrupts. When the interrupt fires, there is an automatic DI that gets run, so you need to undo it.

Wow i missed this while reading my own code >.<

     di
     ld hl,interrupt
     ld de,8A8Ah
     ld bc,interrupt_end - interrupt
     ldir

     ld hl,8000h
     ld de,8001h
     ld bc,257
     ld (hl),8Ah
     ldir
     ld a,%00001011
     out (3),a
     ld a,80h
     ld i,a
     im 2

made a few changes thats the only differences in my code from yours if that doesnt do it idk what it is

The current one is the one up at the top with the changes suggested.

Okay, well this is the current version that I am toying with. I added some code because it seemed to recursively call itself and I wanted to fix that a little.


interrupt:
;     or a \ ret nc
     push af
     push bc
     push de
     push hl
     ld hl,(progPtr)
     push hl
     .db 21h
IprogPtr:
     .dw 0
     ld a,h \ or l
     jr z,EndExec
 jr nz,$
       ld (progPtr),hl
       ld (IprogPtr2),hl
       sbc hl,hl \ ld (IprogPtr),hl
       call ParserNext
       .db 21h
IprogPtr2:
       .dw 0
       ld (IprogPtr),hl
EndExec:
     sub a
     out (3),a
     ld a,%00001011
     out (3),a
     pop hl
     ld (progPtr),hl
     pop hl
     pop de
     pop bc
     pop af
     ei
     ret
interrupt_end:
EDIT: I have the jr nz,$ for debugging puproses

After the call to ParserNext, IprogPtr is never updated. I'm not sure if ParserNext is supposed to advance any pointers, but it certainly won't here. Also, for those of us who don't have the Z80 opcode table memorized, you should add a comment for .db 21h that says ; ld hl, imm16

The only other thing that comes to mind is that you need to make ensure that ParseNext completes quickly or else the main code won't run. Also, make sure that the routine never EIs. Check to make sure the interrupt vector table is correct. And don't even think of running that from flash.

Okay, thanks! The call actually takes care of the progPtr stuff and that is working fine, but the routine does in fact use EI, so I will try to work around that.
I have ideas >.>

Thanks much! I will see if this works

EDIT: It works! Here is how I fixed it:
In the interrupt, I set a flag and then reset it as it finishes
In the program code, whenever I need to EI, I check that flag first to see if it is okay
And it works now I am now executing Grammer code as an interrupt that updates the LCD

Is there a better way to check if an interrupt is currently executing? I am pretty sure I saw a way, so I will check.

Is there a way to check if an interrupt is currently being executed, though?