x65/macros

x65 macro library

Macros are useful for a variety of custom purposes, x65macro.i aims to provide useful common functions that function like a template library.

These macros deal with simple math, assignments, memory copy and loops.

Operations

The base operations provided by these macros include

• set: Assign a value to the contents of an address
• move: Move the contents of an address to another address
• add: addition
• sub: subtraction
• asrm: arithmetic shift right
• aslm: arithmetic shift left
• neg: negate a number
• abs: make a number positive
• copy: copy memory from one location to another
• for: iterate between two numbers with optional step size
• mnop: insert multiple nop at this point

Decorations

Letter codes following the operations have the following meaning

• b: byte
• w: word (2 bytes)
• t: triple (3 bytes)
• l: long (4 bytes)
• n: number of bytes in value
• c: copy result to target
• i: immediate, for example add a value to the contents of an address
• x: use the x register for operation as a counter or an offset
• y: use the y register for operation
• r: relative; ry=(zp),y
• a: use the contents of an address for operation (16 bits)
• s: custom step size (instead of +1 or -1) for loops
• p: positive
• m: negative
• o: use label pool for counter

Examples

	; $fc = CopyCode
	; for ($fe=$2000; $fe<$4000; $fe += (CodeEnd-CopyCode)) {
	;  memcpy($fe, $fc, CodeEnd-CopyCode)
	; }

	set.w CopyCode, $fc
	for.wsp $2000, $4000, $fe, CodeSegLen
	 copy.ry128 $fc, $fe, CodeSegLen
	forend

	; int $fc
	; $fc >>= 1
	asrm.n $fc,4

	ldx #$fc
	aslm.nx $fc,4

	; int $fc
	; $fc = -$fc

	neg.n $fc,4

	; int $fc = abs($fc)
	abs.n $fc, 4

List of macros and args

set.b / .w / .t / .l Value, Target

• set the contents of an 1-4 byte location to a value
• uses accumulator

move.b / .w / .t / .l / .n Src,Trg

• copy 1-4 (or n) bytes from Src location to Trg location
• uses accumulator

asrm.n Target, Size

• shift a signed multi byte number right
• uses accumulator

asrm.nx Target, Size

• shift a signed multi byte number right offset by the x register
• no registers touched

aslm.n Target, Size

• shift a multi byte number left
• no registers touched

aslm.nx Target, Size

• shift a multi byte number left offset by the x register
• no registers changed

neg.cn Source, Target, Size

• negate and copy a multi byte number
• uses accumulator

neg.n Target, Size

• negate a number in place
• uses accumulator

abs.n Trg, Size

• make a number absolute
• uses accumulator

neg.nx Trg, Size

• negate a number in place offset by the x register
• uses accumulator

add.n Address1, Address2, Target, Bytes

• add contents of two memory locations into a target lcoation
• uses accumulator

sub.n Address1, Address2, Target, Bytes

• Target = Address1 - Address2
• uses accumulator

add.ni Address, Value, Target, Bytes

• add a fixed value to a memory location into a target
• uses accumulator

sub.ni Address, Value, Target, Bytes

• Target = Address - Value
• uses accumulator

add.wi Address, Value, Target

• Subtract 16 bit Value from contents of Address and store at Target
• uses accumulator

sub.wi Address1, Address2, Target

• add contents of two 16 bit addresses into a target 16 bit location
• uses accumulator

mnop Count

• add Count nops

copy.x Source, Target, Size

• copy up to 256 bytes using the x register as a counter
• uses accumulator and x register

copy.y Source, Target, Size

• copy up to 256 bytes using the y register as a counter
• uses accumulator and y register

copy.ry zpSrcPtr,zpTrgPtr,Size

• copy up to 256 bytes using the y register

copy.ry128 zpSrcPtr,zpTrgPtr,Size

• copy up to 128 bytes using the y register

copy.o Src,Trg,Size,PoolZP

• copy more than 256 bytes using zero page label pool addresses
• uses accumulator, x and y register

copy.a Src,Trg,Size

• copy more than 256 bytes using absolute indexed in a loop
• uses accumulator, x and y register

copy.zp Src,Trg,Size,zpTmp1,zpTmp2

• copy more than 256 bytes using two pairs of zero page values
• uses accumulator, x and y register

for.x Start, End

• iterate using the x register from Start to End, End is not inclusive so to iterate from 31 to 0 use for.x 31, -1
• uses x register
• end for loop with forend macro

for.y Start, End

• same as for.x but with the y register
• uses y register
• end for loop with forend macro

copy.ry zpSrcPtr,zpTrgPtr,Size

• copy a fixed length buffer using relative zp y indexing
• size is up to a page, changing Y and A

copy.ry128 zpSrcPtr,zpTrgPtr,Size

• copy up to 128 bytes using the y register

for.w Start, End, Counter

• for loop for 16 bit counter
• uses accumulator
• end for loop with forend macro

for.ws Start, End, Counter, Step

• for loop for 16 bit counter with a step value
• uses accumulator
• end for loop with forend macro

for.wsp Start, End, Counter, Step {

• for (word Counter=start; Counter<end; Counter += Step), Step>0
• uses accumulator

for.wsm Start, End, Counter, Step {

• for (word Counter=start; Counter<end; Counter += Step), Step<0
• uses accumulator

forend

• terminates for loops