In this challenge, your job is to use this architecture spec to create a virtual machine capable of running the included binary.
- Three storage regions
- Memory with 15-bit address space storing 16-bit value
- Eight registers
- An unbounded stack which holds individual 16-bit values
- All numbers are unsigned integers 0..32767 (15-bit)
- All math is modulo 32768; 32758 + 15 => 5
- Each number is stored as a 16-bit little-endian pair (low byte, high byte)
- Numbers 0..32767 mean a literal value
- Numbers 32768..32775 instead mean registers 0..7
- Numbers 32776..65535 are invalid
- Programs are loaded into memory starting at address 0
- Address 0 is the first 16-bit value, address 1 is the second 16-bit value, etc
| Code | Op | Operands | Description |
| 0 | halt | Stop execution and terminate the program | |
| 1 | set | a, b | Set the register <a> to the value of <b> |
| 2 | push | a | Push <a> onto the stack |
| 3 | pop | a | Pop the top element from the stack and write it into <a>. Empty stack = error |
| 4 | eq | a, b, c | Set <a> to 1 if <b> is equal to <c>, otherwise set <a> to 0 |
| 5 | gt | a, b, c | Set <a> to 1 if <b> is greater than <c>, otherwise set <a> to 0 |
| 6 | jmp | a | Jump to <a> |
| 7 | jt | a, b | If <a> is nonzero, jump to <b> |
| 8 | jf | a, b | If <a> is zero, jump to <b> |
| 9 | add | a, b, c | Assign into <a> the sum of <b> and <c> |
| 10 | mult | a, b, c | Assign into <a> the product of <b> and <c> |
| 11 | mod | a, b, c | Assign into <a> the remainder of <b> divided by <c> |
| 12 | and | a, b, c | Assign into <a> the bitwise and of <b> and <c> |
| 13 | or | a, b, c | Assign into <a> the bitwise or of <b> and <c> |
| 14 | not | a, b | Stores 15-bit bitwise inverse of <b> in <a> |
| 15 | rmem | a, b | Read memory at address <b> and write it to <a> |
| 16 | wmem | a, b | Write the value from <b> into memory at address <a> |
| 17 | call | a | Write the address of the next instruction to the stack and jump to <a> |
| 18 | ret | Remove the top element of the stack and jump to it, empty stack = halt | |
| 19 | out | a | Write the ASCII value <a> to the terminal |
| 20 | in | a | Read a character from the terminal and write its ASCII code to <a> |
| 21 | noop | No operation |