SDIO_ReadRegister (changes)
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SDIODriver
» SWI Calls
» SDIO_ReadRegister
SDIO_ReadRegister
(SWI &59004)
| Entry | |
|---|---|
| R0 | register number: |
| Index meaning | |
| 0 = wired AND of memory OCR register(s) for slot (4 bytes) | |
| 1 = IO OCR register (4 bytes) | |
| 2 = CID register (15 bytes excluding CRC byte) | |
| 3 = CSD register (15 bytes excluding CRC byte) | |
| 4 = SCR register (8 bytes) | |
| R1 | Bits 0 – 7 = slot number |
| Bits 8 – 15 = bus number | |
| Bits 16 – 31 RCA | |
| R2 | Pointer to buffer (assumed large enough for the register selected) |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Preserved |
| R2 | Preserved |
Use
This SWI is used to read and cache certain registers as part of the process of scanning each slot.
Re-entrancy
This SWI is not re-entrant.
Notes
The buffer is filled in with register contents, stored in little-endian order.
This SWI makes available for the convenience of other modules. An error is generated for unknown register index values, or if the specified card does not provide the specified register.
See also
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