| C64 ROM | Routines |
| Prev: EF4A | Up: Map | Next: EF7E |
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Used by the routine at FED6.
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| EF59 | A6 A9 | LDX $A9 | get start bit check flag | |
| EF5B | D0 33 | BNE $EF90 | if no start bit received go ?? | |
| EF5D | C6 A8 | DEC $A8 | decrement receiver bit count in | |
| EF5F | F0 36 | BEQ $EF97 | if the byte is complete go add it to the buffer | |
| EF61 | 30 0D | BMI $EF70 | ||
| EF63 | A5 A7 | LDA $A7 | get the RS232 received data bit | |
| EF65 | 45 AB | EOR $AB | EOR with the receiver parity bit | |
| EF67 | 85 AB | STA $AB | save the receiver parity bit | |
| EF69 | 46 A7 | LSR $A7 | shift the RS232 received data bit | |
| EF6B | 66 AA | ROR $AA | ||
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This entry point is used by the routine at EF97.
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| EF6D | 60 | RTS | ||
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This entry point is used by the routine at EF97.
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| EF6E | C6 A8 | DEC $A8 | decrement receiver bit count in | |
| EF70 | A5 A7 | LDA $A7 | get the RS232 received data bit | |
| EF72 | F0 67 | BEQ $EFDB | ||
| EF74 | AD 93 02 | LDA $0293 | get pseudo 6551 control register | |
| EF77 | 0A | ASL A | shift the stop bit flag to Cb | |
| EF78 | A9 01 | LDA #$01 | + 1 | |
| EF7A | 65 A8 | ADC $A8 | add receiver bit count in | |
| EF7C | D0 EF | BNE $EF6D | exit, branch always | |
| Prev: EF4A | Up: Map | Next: EF7E |