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for ARM devices
OS_Byte 221 - 228
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_Byte
» OS_Byte 221 – 228
OS_Byte 221 – 228
(SWI &06)
| Entry | |
|---|---|
| R0 | 221 – 228 (&DD – &E5) |
| R1 | EOR value |
| R2 | AND value |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Previous value |
| R2 | Corrupted |
Meaning of value passed by R0
| R0 | Range Affected | Default Value | Effect |
|---|---|---|---|
| 221 | &C0 – &CF | 1 | Function keys (Print, F1-F9, cursor keys and copy if acting as function keys) |
| 222 | &D0 – &FF | &80 | Return buffer code – 16 |
| 223 | &E0 – &FF | &90 | Return buffer code – 16 |
| 224 | &F0 – &FF | 0 | Discard |
| 225 | &80 – &8F | 1 | Function keys (F10-F12, Insert) |
| 226 | &90 – &9F | &D0 | Return buffer code |
| 227 | &A0 – &AF | &E0 | Return buffer code |
| 228 | &B0 – &BF | &F0 | Return buffer code |
Use
The purpose of this call is to read or write the interpretation of input values &80-&FF, which includes codes generated by the function keys.
Notes
The 128 buffer codes are divided into 8 blocks, and the block affected is chosen by R0. The value generated via R1 and R2 determines the interpretation of buffer codes:
| Value | Interpretation |
|---|---|
| 0 | Discard |
| 1 | Expand function key number (code MOD 16) |
| 2 | Insert 0 byte followed by code |
| 3 – 255 | Insert (code MOD 16) + value |