Some Assmbly Extensions

[VK6TT]

Here are some extension I found really useful for speeding up my code. ]C@L is really good for reading hardware registers. They might be worth including in the library?

: ]C@  \ like "[ a ] LITERAL C@" for first 256 bytes of RAM
  POSTPONE [
  $C6 C, ,   \  LD  A,a
  $5A C,     \  DECW X  
  $7F C,     \  clear high byte 
  $5A C,     \  DECW X
  $F7 C, ]    \ LD  (X),A
; IMMEDIATE

: ]C@L  \ like "[ a ] LITERAL C@" for longmem
  POSTPONE [
  $5A C,     \  DECW X  
  $C6 C, ,  \  LD  A,longmem
  $F7 C,     \ LD  (X),A
  $5A C,     \  DECW X
  $7F C,     \  clear high byte 
  ]
; IMMEDIATE

I also use the following occasionally which may be useful:

: RCF $98 C, ; IMMEDIATE \ reset carry flag
: SCF $99 C, ; IMMEDIATE \ set carry flag
: CLR_A  $4F C, ; IMMEDIATE \ clear accum
: ]LDA ( c -- ) $B6 C, C, ] ; IMMEDIATE \ load byte @ c into accum
: ]ADC ( c -- ) $B9 C, C, ] ; IMMEDIATE \ add byte at c to accumulator
: ]LDA>M ( c -- ) $B7 C, C, ] ; IMMEDIATE \ save A to memory

\ rotate byte logical left/right through carry
: ]RLC ( c -- ) $39 C, C, ] ; IMMEDIATE 
: ]RRC ( c -- ) $36 C, C, ] ; IMMEDIATE 

: ]INC ( A -- ) $3C C, C, ] ; IMMEDIATE \ Fastest way to add 1 to MSB of VARIABLE