Opcode Mnemonic Meaning Address Mode Status Bits
         

00000

STOP

Stop Execution

U

 

         

00001

LOADR

R := Oprnd

idsx

NZ

00010

STORER

Oprnd := R

dsx

 

00011

ADDR

R := R + Oprnd

idsx

NZVC

00100

SUBR

R := R - Oprnd

idsx

NZVC

         

00101

ANDR

R := R AND Oprnd

idsx

NZ

00110

ORR

R := R OR Oprnd

idsx

NZ

00111

NOTR

R := NOT R

U

NZ

         

01000

ASLR

C := most significant bit

R := arithmetic shift left R

U

NZVC

01001 ASRR C := least significant bit

R := arithmetic shift right R

U NZC
         
01010 LDBYTR R := byte Oprnd idsx NZ
01011 STBYTR byte Oprnd := R dsx  
         
01100 LOADB B := Oprnd idsx NZ
01101 ADDSP SP := SP + Oprnd i NZVC
         
01110 BR PC := Oprnd ix  
01111 BRLE if NZVC =  <= then PC := Oprnd ix  
10000 BRLT if NZVC =  < then PC := Oprnd ix  
10001 BREQ if NZVC =  = then PC := Oprnd ix  
10010 BRNE if NZVC =  /= then PC := Oprnd ix  
10011 BRGE if NZVC =  >= then PC := Oprnd ix  
10100 BRGT if NZVC =  > then PC := Oprnd ix  
         
10101 BRV if V = 1 then PC := Oprnd ix  
10110 BRC if C = 1 then PC := Oprnd ix  
         
10111 COMPR R - Oprnd idsx NZVC
         
11000 JSR SP := SP -2

Mem[SP] := PC

PC := Oprnd

ix  
11001 RTS PC := Mem[SP]

SP := SP +2

U  
11010 RTI return from interrupt U  
         
11011 CHARI byte Oprnd := input dsx  
11100 CHARO output := byte Oprnd idsx  
11101 DECI Oprnd := input dsx NZV
11110 DECO output := Oprnd idsx  

11111

HEXO

output := Oprnd

idsx

 

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