monitor integration - more work on memory dump

src/mon_m65/mon_command_memory.s

@@ -0,0 +1,65 @@
+
+Mon_Memory:
+
+   jsr  Set_MODE_80
+   lda  #$00
+   sta  Adr_Mode             ; by default use C64-style addressing
+
+   jsr  Get_Addr_To_LAC      ; get 1st parameter (start address)
+   +beq Mon_Error
+   jsr  LAC_To_LPC           ; Long_PC = start address
+
+   jsr  Get_Addr_To_LAC      ; get 2nd parameter (end address)
+   bne  @calcdiff
+
+   lda  #$10                 ; by default display 16 rows
+   sta  Long_CT+0
+   lda  #$00
+   sta  Long_CT+1
+   sta  Long_CT+2
+   sta  Long_CT+3
+
+   bra  @loop
+
+@calcdiff:
+   jsr  LAC_Minus_LPC        ; Long_CT = range
+   +bcc Mon_Error            ; error if negative range
+
+   ldx  #$04                 ; for 80 character mode - 16 (2^4) bytes/line
+   bbr7 MODE_80,@shift
+   dex                       ; for 40 character mode - 8  (2^3) bytes/line
+
+@shift:
+   clc
+   ror  Long_CT+3
+   ror  Long_CT+2
+   ror  Long_CT+1
+   ror  Long_CT+0
+
+   dex
+   bne  @shift               ; at the ned of loop Long_CT contains number of rows to show minus 1
+
+@loop:
+
+   jsr  Dump_Row
+   jsr  STOP
+   beq  @exit                ; end if STOP pressed
+
+   sec                       ; XXX consider moving this to separate subroutine
+   lda  Long_CT+0
+   sbc  #$01
+   sta  Long_CT+0
+   lda  Long_CT+1
+   sbc  #$00
+   sta  Long_CT+1
+   lda  Long_CT+2
+   sbc  #$00
+   sta  Long_CT+2
+   lda  Long_CT+3
+   sbc  #$00
+   sta  Long_CT+3
+   bcs  @loop
+
+@exit:
+
+   jmp Main