view lib/alib/jsr_cmd.a @ 2765:0bd16cca86b7

Updated rules.mak for all the os9 format's to format the entire disk. People were having some issues with the disk images not being formatted to their full capacity and preventing some functions from working.
author drencor-xeen
date Thu, 17 Jan 2013 11:03:26 -0600
parents 7d70b7e1cb21
children aaba193af04f
line wrap: on
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***************************************

* Subroutine to jsr to subroutine from 1 character command table

* OTHER MODULES NEEDED: none

* ENTRY: A=1 char command
*        X=start of jump table

* EXIT:  CC carry set if entry not found 
*        all other regs can be modified by subs

* Note format of table: each entry is three bytes
*                       0-match character (command)
*                       1..2-offset to routine

* It is the user's job to set commands to proper case for matching...

* end of table=NULL

* sample table:  fcc /A/
*                fdb routineA-*
*                fcc /B/
*                fdb routineB-*
*                fcb 0 


 nam Jsr to 1 char Command
 ttl Assembler Library Module

 psect JSR_CMD,0,0,0,0,0

JSR_CMD:
 tst ,x end of table?
 beq jsrerr

 cmpa ,x+ found match?
 beq docmd yes, go do it

 leax 2,x next entry
 bra JSR_CMD

* no match found, return with carry set

jsrerr
 coma set error flag
 rts

* command found, do call and return
  
docmd
 ldd ,x get offset to routine
 jsr d,x
 andcc #%11111110 clear carry
 rts

 endsect