Procedure size? Need halp

[carsonmyers]

so I have this working procedure that is basically like function 09h of int 21h except it terminates at 00h, and it uses 01h-04h as control characters that determine the style of the text.

I wrote it in the main procedure of a test program to get it working, and then I put it in its own procedure in a larger program. When I run it from the larger program, I get this error:

"title: 16 bit MS-DOS Subsystem

Command Prompt - cmp
NTVDM has encountered a System Error
Access is denied.
Choose 'Close' to terminate the application
Close | Ignore"

I can't really ignore it. Anyways, I narrowed the cause of this error down to a procedure without a "RET" statement. But it has a return statement at the end. If I just put RET in the procedure, it runs, if I put all of the code back into the test program (main procedure), it runs. So I'm thinking maybe there's a maximum size for a procedure that is called? It is quite long, I haven't tried to slim it down at all, I'm not sure if I really can. Anyway, here's the procedure:

outp proc
		
	push cx
	push bx
	xor cx,cx
	xor bx,bx
nexch:  mov si,dx
	push dx
	add si,cx
	push cx
	mov al,[si]
	cmp al,00h
	jnz nndpr
	jmp endpr
nndpr:  cmp al,0dh				;LINE FEED
	jnz not0d
	mov ah,03h
	int 10h
	cmp dh,24d
	jz scwin
	inc dh
	mov ah,02h
	int 10h
	jmp gnext
scwin:  mov ax,0601h
	xor cx,cx
	mov dh,24d
	mov dl,79d
	mov bl,attrWHT
	int 10h
	jmp gnext
not0d:  cmp al,0ah				;CARRIAGE RETURN
	jnz not0a
	mov ah,03h
	int 10h
	mov dl,00h
	mov ah,02h
	int 10h
	jmp gnext
not0a:  cmp al,01h				;WHITE
	jnz not01
	mov bl,attrWHT
	mov attrCUR,bl
	jmp gnext
not01:  cmp al,02h				;GREEN
	jnz not02
	mov bl,attrGRN
	mov attrCUR,bl
	jmp gnext
not02:  cmp al,03h				;YELLOW
	jnz not03
	mov bl,attrHLT
	mov attrCUR,bl
	jmp gnext
not03:  cmp al,04h				;EDIT/HEADER
	jnz not04
	mov bl,attrEDT
	mov attrCUR,bl
	jmp gnext
not04:  mov ah,09h
	mov bl,attrCUR
	mov cx,01h
	int 10h
	mov ah,03h
	int 10h
	inc dl
	mov ah,02h
	int 10h
gnext:  pop cx
	pop dx
	inc cx
	jmp nexch
endpr:	pop bx
	pop cx
	ret

I'm using TASM, and the model of the program is small... I tried making it "Large" and "Huge" to see how that would affect it but it said there was a problem with my call statement in the main procedure (Forward reference needs override). Has anyone run into something similar to this? How can I fix it and make it work?

Oh, and I tried doing something like this:

outp proc

	jmp strprc
endprc: ret
strprc: ...
	...
	...
	...
	jmp endprc

outp endp

the procedure did its job but it wouldn't return afterward, the cursor just sat there blinking and I couldn't input anything (text, ctrl-c, etc)

[carsonmyers]

so I figured out if I pop the stack into ax at the very beginning of the procedure (the return pointer), move that value into a variable I have saved, then push it back, then at the end of the procedure, move the variable into ax and push it again, then it will return properly, so I suppose I'm just not unwinding the stack correctly... Still I wonder why access to the procedure is denied if the RET statement is too far away? I'd like to just put it at the end and save all those unnecessary jumps