The condition codes are as defined below:
BIT NO. | LABEL | CONDITION CODE |
0 | C | |
1 | V | Overflow |
2 | Z | Zero |
3 | N | Negative |
4 | I | Interrupt mask |
5 | H | Half carry |
In the above example the condition code of "3C" can be interpreted as follows:
3C16 = | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 0 |
| BIT 7 | BIT 6 | BIT 5 | BIT 4 | BIT 3 | BIT 2 | BIT 1 | BIT 0 |
Below are two examples of how the R command works. Assume that this small program was entered to change certain registers.
$M 0100 |
|
| |
$0100 CE | 8E | LOADS STACK POINTER TO 100 | |
$0101 12 | 10 |
| |
$0102 34 | 00 |
| |
$0103 86 | CE | LOAD INDEX REGISTER WITH 1234 | |
$0104 00 | 12 |
| |
$0105 C6 | 34 |
| |
$0106 FF | 86 | LOAD ACCUMULATOR A WITH 00 | |
$0107 FD | 00 |
| |
$0108 08 | C6 | LOAD ACCUMULATOR B WITH FF | |
$0109 23 | FF |
| |
$010A | 67 | 7E | JUMP BACK TO SWTBUG CONTROL |
$010B | F7 | E0 |
|
$010C | 60 | E3 |
|
$010D | DD |
|
|
AT THIS POINT THE STATUS WILL NOT BE PUSHED ON THE STACK
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