; This patch causes the CCP of a cp/m 2.x system to look on drive A
; when you are logged into a drive other than A and call for a .COM
; file that does not exist on that drive.  Giving an explicit drive
; reference overrides this feature, so that you can always force
; the file to be loaded from a specific drive.
;
msize   equ     60              ; set this to your nominal system size
;
cpmb    equ     (msize-20)*1024+3400h   ; start of CCP in given sys size
;
       org     cpmb+6dbh
       jz      patch           ; replaces "jz cpmb+76bh"
;
       org     cpmb+7f2h       ; replaces an unused area of NOP's
patch:
       lxi     h,cpmb+7f0h     ; get drive from current command
       ora     m               ; accum was 0 on entry, so this fetches drive
       jnz     cpmb+76bh       ; command has explicit drive...give error
       inr     m               ; force explicit reference to drive A
       lxi     d,cpmb+7d6h     ; we need de set up when we
       jmp     cpmb+6cdh       ; re-enter ccp
;
       end

You are viewing proxied material from gopher.floodgap.com. The copyright of proxied material belongs to its original authors. Any comments or complaints in relation to proxied material should be directed to the original authors of the content concerned. Please see the disclaimer for more details.