Difference between revisions of "OSRDCH"
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==Specification== | ==Specification== | ||
{| cellpadding="0" cellspacing="0" | {| cellpadding="0" cellspacing="0" | ||
| − | | | + | | 6502 || Z80 || 6809 || PDP11 || 80x86 || 32016 || ARM || RISC-V || align="left" | '''On entry:''' || align="left" | '''On exit:''' |
|- align="center" valign="top" | |- align="center" valign="top" | ||
| − | | A || A || A || R0 || AL || R1 || R0 || align="left" | - || align="left" | = byte read | + | | A || A || A || R0 || AL || R1 || R0 || A0 || align="left" | - || align="left" | = byte read |
|- align="center" valign="top" | |- align="center" valign="top" | ||
| − | | || || || || || || || align="left" | || align="left" | Cy=Error status | + | | || || || || || || || || align="left" | || align="left" | Cy=Error status |
|} | |} | ||
| − | If an error occured (usually, Escape being pressed), then the carry flag is set on exit. If the error was Escape, then A will be &1B. | + | If an error occured (usually, Escape being pressed), then the carry flag is set on exit. If the error was Escape, then A will be &1B regardless of the defined Escape character. |
==Calling from BBC BASIC== | ==Calling from BBC BASIC== | ||
| Line 24: | Line 24: | ||
* 80x86 Entry Address: INT &46, vectors via 0000:0118 | * 80x86 Entry Address: INT &46, vectors via 0000:0118 | ||
* 32000 Entry Address: SVC &05 | * 32000 Entry Address: SVC &05 | ||
| − | * | + | * PDP11 Entry Address: EMT 5, vector &05 |
* ARM Entry Address: SWI &04 "OS_ReadC", vector &04 | * ARM Entry Address: SWI &04 "OS_ReadC", vector &04 | ||
| + | * RISC-V Entry Address: ECALL &AC0005 | ||
==Implementations== | ==Implementations== | ||
Revision as of 20:20, 10 September 2023
Waits for a character from the current input stream.
Specification
| 6502 | Z80 | 6809 | PDP11 | 80x86 | 32016 | ARM | RISC-V | On entry: | On exit: |
| A | A | A | R0 | AL | R1 | R0 | A0 | - | = byte read |
| Cy=Error status |
If an error occured (usually, Escape being pressed), then the carry flag is set on exit. If the error was Escape, then A will be &1B regardless of the defined Escape character.
Calling from BBC BASIC
-
b%=GETcalls OSRDCH. -
b$=GET$calls OSRDCH.
Entry points
- BBC BASIC Entry Address: &FFE0
- 6502 Entry Address: &FFE0, vectors via &0210
- Z80 Entry Address: &FFE0, vectors via &FFE1
- 6809 Entry Address: &FFE0, vectors via &FFE1
- 80x86 Entry Address: INT &46, vectors via 0000:0118
- 32000 Entry Address: SVC &05
- PDP11 Entry Address: EMT 5, vector &05
- ARM Entry Address: SWI &04 "OS_ReadC", vector &04
- RISC-V Entry Address: ECALL &AC0005
Implementations
All MOSs implement OSRDCH. Some systems allow BGET#0 to read from the character input stream via OSRDCH.
Jgharston 17:02, 6 November 2009 (UTC)
