Assembler and simulator for a 8 Bit Computer made in CircuitGrid
Computer layout and some example programs demonstrated in this video: https://www.youtube.com/watch?v=xGdsyXCmmoE
Everything after a # is a comment.
# this is a comment
Operands can be constants, variables(&) or pointer(*):
# Example for constant:
x = 69 #set x to 69
# Example for variable:
x = &y #set x to the value in y
# Example for pointer:
x = *y #set x to the value in the address stored in y
Operations can't be concatenated!
x = 1 + 3 + 5 #not okay :(
x = 1 + 3 #okay :)
x = &x + 5 #okay :)
if &x + 1 == 2 #not okay :(
The Preprocessor replaces all variables with their addresses. So this...
var x 0
var y 1
x = y
&x = 2
...will be converted to this...
0 = 1
&0 = 2
which will set the value in address 0 to 1
and sets the value in the address, which is stored at address 0, to 2.
After execution address 0 has value 1 and address 1 has value 2
Labels can be defined with a colon
:main
JUMP main
If conditions run the next indented scope if the condition is true.
Indentations have to be Tabs!
if &x >= 2
#do something
y = 1 + 1
Checking user input:
All USER_IN values: UP, DOWN, LEFT, RIGHT, A, B
Example for USER_IN if condition:
if USER_IN == DOWN
#do something
| Keyword | Description | Example |
|---|---|---|
| var | declares a variable and its address | var x 0 |
| END | ends the program | END |
| JUMP | jump to a label | JUMP main |
| SWAP | updates the screen with the last 32 bytes in RAM | SWAP |
| SHOW | displays the given value | SHOW &x |
| DEBUG | pauses the execution (Breakpoint) | DEBUG |
| << | bitshift left | x = &y << 3 |
| >> | bitshit right | x = &y >> 3 |
| = | assigns a value | x = 42 |
| + | adds two values | x = &x + &y |
| - | subtracts two values | x = &x - &y |
| * | multiplies two values | x = &x * &y |
| / | divides two values | x = &x / &y |
| % | modulo operation | x = &x % 2 |
| not | bitwise NOT | x = not &y |
| | | bitwise OR | x = 12 | 6 |
| !| | bitwise NOR | x = 12 !| 6 |
| ^ | bitwise XOR | x = 12 ^ 6 |
| !^ | bitwise XNOR | x = 12 !^ 6 |
| & | bitwise AND | x = 12 & 6 |
| !& | bitwise NAND | x = 12 !& 6 |
| popcnt | gets the number of ones in value | x = popcnt 69 |
| if | checks a condition | if &x != 2 |
| if | checks user input | if USER_IN == UP |
Some example scripts are in "computer simulator/code_archive"
Errors from compilation dont always make sense because i didn't bother to write error-handeling for every case