Reinstating the KT8!!!

KT8 opcodes v3-.txt

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+Proposed Op codes for KT8 processor
+Created - CAK 2-11-2014
+
+KT8 (Krauter/Terpstra 8-bit) is a super simple processor that works with just 8-bit instructions.
+
+KT8 Has:
+- 8-bit wide instructions in a separate bank of program memory. 
+- Three registers for arithmetic:
+	A = input 1
+	B = input 2
+	R = result
+- 32 bytes of RAM memory[0-31]. Some of these memory locations could do special things.
+
+Op Codes:
+
+Bits        OP Name        Description
+
+000 aaaaa - LOADA aaaaa : copy from RAM address to register A
+001 aaaaa - LOADB aaaaa : copy from RAM address to register B
+010 aaaaa - SAVE aaaaa : copy from register R to RAM address
+
+0110 xxxx - LOWBITS xxxxxxxx : save 4bits=xxxx to lower bits[0-3] of B
+key store  000000001
+disp write  0000000001 
+key to disp 00000000001 
+1000 0000 - ADD          : R = A + B  
+1000 0001 - SUB          : R = A - B
+1000 0010 - AND          : R = A AND B
+1000 0011 - OR           : R = A OR B
+1000 0100 - XOR          : R = A XOR B
+1000 0101 - INVA	 : R = bit inverse A
+1000 0110 - INVB	 : R = bit inverse B
+1000 0111 - SWAPA	 : swap values between R and A
+1000 1000 - SWAPB	 : swap values between R and B
+1000 1001 - LSHIFT	 : shift bits in R to the left
+1000 1010 - RSHIFT	 : shift bits in R to the right
+1000 1011 - CLEAR	 : set R to zero
+1000 1100 - INC		 : add 1 to R
+1000 1101 - DEC		 : subtract 1 from R
+
+1100 xxxx - FJMP xxxx : move program counter forward by xxxx instructions
+1101 xxxx - BJMP xxxx : move program counter back by xxxx instructions
+11100000 - SKIPZ : if R is zero move program counter forward 2 instead of 1
+11100001 - SKIPNZ : if R is not zero move program counter forward 2 instead of 1
+
+11111111 - RESET : put program counter back to zero