# HG changeset patch
# User Neal Crook <foofoobedoo@gmail.com>
# Date 1496092782 -3600
# Node ID 5e48668f30b2859cf8f2e65b47e4a64d429fe75b
# Parent  147d2267d9b8688cd3a5cfd6c7d7d312a9204651
dmem.asm: Annotate comments, remove trailing whitespace

Annotated comments from original source listing in "Inside OS9 Level II".

CRC identical.

diff -r 147d2267d9b8 -r 5e48668f30b2 level2/cmds/dmem.asm
--- a/level2/cmds/dmem.asm	Mon May 29 20:15:36 2017 +0100
+++ b/level2/cmds/dmem.asm	Mon May 29 22:19:42 2017 +0100
@@ -1,8 +1,13 @@
 ********************************************************************
 * DMem - Dump memory from system
 *
+* dmem  <block> <offset> [<length>] ! dump
+* dmem -<proc#> <offset> [<length>] ! dump
+*
 * $Id$
 *
+* From "Inside OS9 Level II", by Kevin Darling
+*
 * Edt/Rev  YYYY/MM/DD  Modified by
 * Comment
 * ------------------------------------------------------------------
@@ -18,107 +23,116 @@
          use   defsfile
          endc
 
-tylg     set   Prgrm+Objct   
+tylg     set   Prgrm+Objct
 atrv     set   ReEnt+rev
 rev      set   $00
 edition  set   2
 
-         mod   eom,name,tylg,atrv,start,size
+         mod   eom,name,tylg,atrv,entry,msize
 
-u0000    rmb   1
-u0001    rmb   1
-u0002    rmb   1
-u0003    rmb   2
-u0005    rmb   3
-u0008    rmb   64
-u0048    rmb   1
-u0049    rmb   447
-u0208    rmb   4296
-size     equ   .
+acc      rmb   2
+input    rmb   1
+offset   rmb   2
+dlen     rmb   2
+id       rmb   1
+prcdsc   rmb   512
+buffer   rmb   4296
+msize    equ   .
+
+dat      equ   prcdsc+$40
 
 name     fcs   /DMem/
          fcb   edition
 
-L0012    clr   <u0000
-         clr   <u0001
-L0016    lda   ,x+
+hexin    clr   <acc
+         clr   <acc+1
+
+hexin01  lda   ,x+
          cmpa  #C$SPAC
-         beq   L0046
+         beq   hexrts
          cmpa  #C$CR
-         beq   L0046
+         beq   hexrts
          suba  #$30
          cmpa  #$0A
-         bcs   L002A
-         anda  #$07
+         bcs   hex2             0-9
+         anda  #$07             A-F
          adda  #$09
-L002A    lsla
+hex2     lsla
          lsla
          lsla
          lsla
-         sta   <u0002
-         ldd   <u0000
-         rol   <u0002
+         sta   <input
+         ldd   <acc             get accumulator
+         rol   <input
          rolb
          rola
-         rol   <u0002
+         rol   <input
          rolb
          rola
-         rol   <u0002
+         rol   <input
+         rolb
+         rola
+         rol   <input
          rolb
          rola
-         rol   <u0002
-         rolb
-         rola
-         std   <u0000
-         bra   L0016
-L0046    leax  -1,x
-         ldd   <u0000
+         std   <acc
+         bra   hexin01
+hexrts   leax  -1,x
+         ldd   <acc
          rts
 
-start    lbsr  L0128
-         lbeq  L0119
-         cmpa  #'-
-         bne   L006D
-         leax  1,x
-         bsr   L0012
+entry    lbsr  skipspc          skip leading spaces
+         lbeq  badnum           ..was it CR?
+         cmpa  #'-              else is it #id?
+         bne   entry0            ..no
+
+         leax  1,x              yes, skip '-'
+         bsr   hexin            get id number
          tfr   b,a
          pshs  x
-         leax  >u0008,u
-         os9   F$GPrDsc 
-         lbcs  L00BC
+         leax  >prcdsc,u
+         os9   F$GPrDsc         get that process descriptor
+         lbcs  error
          puls  x
-         bra   L0073
-L006D    bsr   L0012
-         clr   <u0048
-         stb   <u0049
-L0073    lbsr  L0128
-         lbeq  L0119
-         lbsr  L0012
-         std   <u0003
-         lbsr  L0128
-         beq   L0092
-         lbsr  L0012
+         bra   entry1
+
+entry0   bsr   hexin            get block #
+         clr   <dat             set in fake DAT image
+         stb   <dat+1
+
+entry1   lbsr  skipspc          get offset
+         lbeq  badnum
+         lbsr  hexin
+         std   <offset
+         lbsr  skipspc          get possible offset
+         beq   entry2
+
+         lbsr  hexin
          cmpd  #$1000
-         bls   L0095
+         bls   entry3
          ldd   #$1000
-         bra   L0095
-L0092    ldd   #$0100
-L0095    std   <u0005
-         leax  >u0048,u
-         tfr   x,d
-         ldy   <u0005
-         ldx   <u0003
+         bra   entry3
+entry2   ldd   #$0100
+
+entry3   std   <dlen
+
+         leax  >dat,u
+         tfr   x,d              D=DAT image pointer
+         ldy   <dlen            Y=count
+         ldx   <offset          X=offset within DAT image
          pshs  u
-         leau  >u0208,u
-         os9   F$CpyMem 
+         leau  >buffer,u
+         os9   F$CpyMem
          puls  u
-         bcs   L00BC
-         ldy   <u0005
-         leax  >u0208,u
+         bcs   error
+
+         ldy   <dlen
+         leax  >buffer,u        point within buffer
          lda   #$01
-         os9   I$Write  
-L00BB    clrb  
-L00BC    os9   F$Exit   
+         os9   I$Write
+
+bye      clrb
+error    os9   F$Exit
 
 HelpTxt  fcc   "Use: DMem <block> <offset> [<length>] ! dump"
          fcb   C$LF
@@ -126,17 +140,18 @@
          fcb   C$CR
 HelpTxtL equ   *-HelpTxt
 
-L0119    leax  >HelpTxt,pcr
-L011D    ldy   #HelpTxtL
+badnum   leax  >HelpTxt,pcr
+         ldy   #HelpTxtL
          lda   #$02
-         os9   I$WritLn 
-         bra   L00BB
-L0128    lda   ,x+
+         os9   I$WritLn
+         bra   bye
+
+skipspc  lda   ,x+
          cmpa  #C$SPAC
-         beq   L0128
+         beq   skipspc
          leax  -1,x
          cmpa  #C$CR
-         rts   
+         rts
 
          emod
 eom      equ   *