4BoD
4BoD (4 Bits of DOOM) is a hyper-minimalist fantasy console inspired by Milton Bradley Microvision. It was created as an entry for FC Dev jam by puarsliburf games in 2017.
Capabilities
Program memory: 3072b (256 12-bit instructions).
RAM: 16 nibbles (64b).
Screen: 16x16 (1:1) 1-bit.
Instruction set: 16 instructions.
Sounds: no.
Instruction Set
Instructions set (from)
OP |A |B |Description
0000 - NOP
0001 AAAA - Sets the accumulator to the value stored at memory position A
0010 AAAA - Sets memory position A to the value stored in the accumulator
0011 AAAA - Sets the accumulator to A
0100 - Sets the accumulator to the buttons that have been pressed
- Ones place = left button
- Twos place = right button
- Fours place = up button
- Eights place = down button
0101 - Increments the accumulator (Do this 15 times to make a subtraction by overflow)
0110 - Clears the screen
0111 - Shifts the accumulator left
1000 - Shifts the accumulator right
1001 AAAA BBBB - Sets the accumulator to pixel position memory A, memory B
1010 AAAA BBBB - Flips pixel position memory A, memory B
1011 AAAA - Sets a flag called A (Flag 15 is reserved, if you jump to it the program ends)
1100 AAAA - Jumps to flag memory position A
1101 AAAA - Only perform next action if memory position A is equal to the accumulator
1110 AAAA - Only perform next action if memory position A is greater than the accumulator
1111 AAAA - Only perform next action if memory position A is less than the accumulator