acme/docs/cputypes/all.txt

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ACME
...the ACME Crossassembler for Multiple Environments
--- cpu types ---
ACME supports the following cpu types (shown here as a sort of family
tree):
6502 standard
|
|\_nmos6502 (=6510) + undocumented opcodes
|
|\_c64dtv2 + BRA/SAC/SIR and some (not all!) undocumented
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\_65c02 + BRA/PHX/PHY/PLX/PLY/STZ/TRB/TSB/...
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|\_65816 16 bit regs, 24 bit address space, ...
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\_r65c02 + bit manipulation instructions
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|\_w65c02 + STP/WAI
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\_65ce02 + Z reg, long branches, ...
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\_4502 + MAP/EOM
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\_m65 + 32-bit pointers, 32-bit 'Q' register
!cpu 6502
This is the official instruction set of the original NMOS 6502 CPU
designed by MOS (later CSG).
There are 151 documented opcodes.
ACME does not use "A" to indicate "accumulator addressing"; just write
the mnemonic without any argument: "LSR" will work, "LSR A" won't.
!cpu nmos6502
This instruction set includes the undocumented ("illegal") opcodes of
the NMOS 6502.
See "docs/Illegals.txt" for more info.
!cpu 6510
This is an alias for "nmos6502", because the 6510 cpu (as used in the
C64 computer) is a variant of this type.
!cpu c64dtv2
This is the cpu in version 2 of the C64DTV. It uses a superset of the
6502 instruction set. Features:
- new instructions:
BRA near_target branch always
SAC #$12 set accumulator mapping
SIR #$12 set index register mapping
- support for some (but not all!) of the undocumented opcodes.
!cpu 65c02
This is the CMOS re-design of the 6502. It seems to have also been
available from Rockwell, GTE/CMD and others. Features:
- new instructions:
BRA near_target branch always
PHX/PHY/PLX/PLY push/pull X/Y register
STZ $12 store zero in zp
STZ $12, x store zero in zp, x-indexed
STZ $1234 store zero absolute
STZ $1234, x store zero absolute, x-indexed
TRB $12 test and reset bits in zp
TRB $1234 test and reset bits absolute
TSB $12 test and set bits in zp
TSB $1234 test and set bits absolute
- new addressing modes for existing instructions:
LDA/STA/ADC/SBC ($12) zp indirect
AND/ORA/EOR/CMP ($12) zp indirect
BIT #$12 immediate
BIT $12, x zp, x-indexed
BIT $1234, x absolute, x-indexed
INC increment accumulator
DEC decrement accumulator
JMP ($1234, x) x-indexed indirect
- bugfix for flags in decimal mode
- bugfix for JMP($xxff) instruction
- undocumented opcodes are NOPs (although of different lengths)
There are 178 documented opcodes.
!cpu 65816
This is a superset of 65c02, originally designed by WDC (it seems to
have been available from GTE/CMD as well). Features:
- register sizes can be changed to 16-bit
- 24-bit address space
- several new instructions (including block transfers)
- several new addressing modes for existing instructions
There are 256 documented opcodes, but one of them ("WDM") is reserved
for future expansion.
See "docs/65816.txt" for more info.
!cpu r65c02
This is a superset of 65c02, probably originally by Rockwell. It adds
bit manipulation instructions:
BBR4 $12, near_target branch on bit reset in zp
BBS5 $12, near_target branch on bit set in zp
RMB6 $12 reset memory bit in zp
SMB7 $12 set memory bit in zp
The digit in the mnemonic is the bit number, therefore it must be in
the 0..7 range.
Chips with this instruction set seem to have been available from
Rockwell, GTE/CMD and others.
There are 210 documented opcodes.
!cpu w65c02
This is a superset of r65c02, originating at WDC. It adds two new
instructions:
STP stop (wait for reset)
WAI wait for interrupt
There are 212 documented opcodes.
!cpu 65ce02
This is a superset of r65c02, originating at CSG. Features:
- Z register
- 16-bit stack pointer
- 16-bit branches
- new instructions (including a few 16-bit operations)
- new addressing modes for existing instructions
There is a known bug: SBC does not work correctly in decimal mode.
There are 256 documented opcodes, but one of them ("AUG") is reserved
for future expansion.
ACME uses different mnemonics for old and new (long) branch
instructions:
BEQ near_target old, 8-bit offset
LBEQ far_target new, 16-bit offset
The original datasheet called BRA ("branch always") BRU ("branch
unconditional") instead. ACME accepts both mnemonics.
!cpu 4502
This is basically the same as 65ce02, but
- MAP replaces AUG
- EOM is synonymous to NOP
This cpu core can be found in the CSG4510 chip in the C65.
There are 256 documented opcodes.
!cpu m65
This is a superset of 4502 specified by the MEGA65 project. It uses
NEG:NEG and NOP as prefix bytes to extend the instruction set.
Features:
- "quad mode" (32-bit data operations on virtual register 'Q')
- "long mode" (32-bit pointer addressing for existing mnemonics)
- "quad" and "long" modes can be combined
quad mode introduces several new mnemonics:
LDQ/STQ/CPQ like LDA/STA/CMP
ADCQ/SBCQ like ADC/SBC
ANDQ/EORQ/ORQ like AND/EOR/ORA
ASLQ/LSRQ/ROLQ/RORQ like ASL/LSR/ROL/ROR
INQ/DEQ like INC/DEC
The new mnemonics support all the addressing modes of the original
mnemonics with two exceptions:
- there are no 32-bit immediate arguments
- indirect-z addressing becomes indirect addressing
CAUTION: The STQ instruction clobbers the N and Z flags!
There is no "real" Q register, instead A/X/Y/Z are combined to form
the Q register (A holds lsb, Z holds msb), except for read-modify-
write instructions, where the 32-bit operation is performed without
using A/X/Y/Z.
To load a 32-bit immediate constant into the Q register, use the
+movq macro from the <m65/std.a> library file.
long mode brings a single new addressing mode for eight mnemonics:
LDA [$12], z contents of $12/$13/$14/$15
STA [$12], z plus z form the address
CMP [$12], z
ADC [$12], z
SBC [$12], z
AND [$12], z
EOR [$12], z
ORA [$12], z
quad and long modes combined result in another addressing mode for
eight of the new mnemonics:
LDQ [$12] contents of $12/$13/$14/$15
STQ [$12] form the address
CPQ [$12]
ADCQ [$12]
SBCQ [$12]
ANDQ [$12]
EORQ [$12]
ORQ [$12]
The NOP mnemonic is disabled for this instruction set because its
opcode is re-used internally as a prefix byte.
CAUTION: The !align pseudo opcode still inserts NOPs.