Increment
0: ADD F (00101111)
1: OUT (11100000)
2: JUMP 0 (01100000)
...
F: (DATA) 1 (00000001)
This is a very simple program to count up in 1’s. ADD loads the data at address F into the B register, adds it to the value in the A register, and stores the result in the A register. Then the value in the A register is output and the program jumps back to the beginning.
Fibonacci
0: ADD F (00101111)
1: JUMP_C 9 (01111001)
2: OUT (11100000)
3: STORE_A D (01001101)
4: LOAD_A E (00011110)
5: STORE_A F (01001111)
6: LOAD_A D (00011101)
7: STORE_A E (01001110)
8: JUMP 0 (01100000)
9: HALT (11110000)
...
E: (DATA) 1 (00000001)
F: (DATA) 0 (00000000)
This program calculates the Fibonacci sequence until it requires more than 8 bits. It adds the value at address F to the A register. If the addition overflows it jumps to address 9 and halts. Otherwise, it moves some data around to save the current value in E and the previous value in F. Then is jumps back to address 0 and repeats.
Multiply 6 by 11 (0x6 x 0xB)
0: LOAD_A F (00011111)
1: STORE_A D (01001101)
2: LOAD_A D (00011101)
3: OUT (11100000)
4: ADD F (00101111)
5: STORE_A D (01001101)
6: LOAD_A E (00011110)
7: SUB C (00111100)
8: JUMP_Z B (10001100)
9: STORE_A E (01001110)
A: JUMP 2 (01100010)
B: HALT (11110000)
C: (DATA) 1 (00000001)
D: (DATA) 0 (00000000)
E: (DATA) B (00001100)
F: (DATA) 6 (00000110)
This program multiplies the 2 numbers stored in E and F. It works by repeatedly adding the value at address F to itself, while subtracting 1 from the value at address E. When the subtraction results in a 0 the program halts.
Manual programming
This video shows the CPU being manually programmed. It is initially running the increment program above. After programming, the value at address F is updated to 5. So the new program counts in 5’s instead of 1’s.
Unmute this video to hear the satisfying THUNKs of the switches.
Bootloading
In this video the CPU is initially running the increment program. After resetting it has switched to the multiply program.