The BBC and Master Computer Public Domain Library
Pop Integer from the BASIC Stack
Submitted by Steve Fewell
Routine: popi
Name: Pop Integer from the BASIC Stack
Starting Address: &BCE6
Entry criteria: None
Exit: IWA contains the value of the most
recent Integer number on the BASIC Stack. The
Basic Stack Pointer is moved up.
Description:
Loads the IWA with the 32-bit Integer pointed to
by the BASIC Stack Pointer. Then move the Stack
Pointer up 4 bytes so that is points to the previous item pushed onto the stack.
Disassembly for the Pop Integer from the BASIC Stack routine
| BCE6 | 160 003 | A0 03 | LDY#&03 | |
| BCE8 | 177 004 | B1 04 | LDA (&04),Y | |
| BCEA | - | 133 045 | 85 2D | STA &2D |
| BCEC | 136 | 88 | DEY | |
| BCED | 177 004 | B1 04 | LDA (&04),Y | |
| BCEF | , | 133 044 | 85 2C | STA &2C |
| BCF1 | 136 | 88 | DEY | |
| BCF2 | 177 004 | B1 04 | LDA (&04),Y | |
| BCF4 | + | 133 043 | 85 2B | STA &2B |
| BCF6 | 178 004 | B2 04 | LDA (&04) | |
| BCF8 | * | 133 042 | 85 2A | STA &2A |
| BCFA | 024 | 18 | CLC | |
| BCFB | 169 004 | A9 04 | LDA#&04 | |
| BCFD | e | 101 004 | 65 04 | ADC &04 |
| BCFF | 133 004 | 85 04 | STA &04 | |
| BD01 | 144 002 | 90 02 | BCC 2 --> &BD05 | |
| BD03 | 230 005 | E6 05 | INC &05 | |
| BD05 | ` | 096 | 60 | RTS |
