diff options
| author | Sadeep Madurange <sadeep@asciimx.com> | 2025-01-19 18:45:05 +0800 |
|---|---|---|
| committer | Sadeep Madurange <sadeep@asciimx.com> | 2025-01-19 18:45:49 +0800 |
| commit | a7644c020c4c2b72fc0f13aeea4be47ba08f1961 (patch) | |
| tree | 4eb34f3b93d81c445af49c1cf81e2ec82a50b3c4 /aliznayem/spi.c | |
| parent | 4c0557793d80cbcc6575b83db9cb3a44feeca229 (diff) | |
| download | smart-home-a7644c020c4c2b72fc0f13aeea4be47ba08f1961.tar.gz | |
Try with aliznayem C port (no luck).
Diffstat (limited to 'aliznayem/spi.c')
| -rw-r--r-- | aliznayem/spi.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/aliznayem/spi.c b/aliznayem/spi.c new file mode 100644 index 0000000..9145109 --- /dev/null +++ b/aliznayem/spi.c @@ -0,0 +1,80 @@ +/* + Copyright (c) 2007 Stefan Engelke <mbox@stefanengelke.de> + + Permission is hereby granted, free of charge, to any person + obtaining a copy of this software and associated documentation + files (the "Software"), to deal in the Software without + restriction, including without limitation the rights to use, copy, + modify, merge, publish, distribute, sublicense, and/or sell copies + of the Software, and to permit persons to whom the Software is + furnished to do so, subject to the following conditions: + + The above copyright notice and this permission notice shall be + included in all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT + HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + DEALINGS IN THE SOFTWARE. + + $Id$ +*/ + +#include <avr/io.h> +#include "spi.h" + +void spi_init() +// Initialize pins for spi communication +{ + SPI_DDR &= ~((1<<MOSI)|(1<<MISO)|(1<<SS)|(1<<SCK)); + // Define the following pins as output + SPI_DDR |= ((1<<MOSI)|(1<<SS)|(1<<SCK)); + + + SPCR = ((1<<SPE)| // SPI Enable + (0<<SPIE)| // SPI Interupt Enable + (0<<DORD)| // Data Order (0:MSB first / 1:LSB first) + (1<<MSTR)| // Master/Slave select + (0<<SPR1)|(0<<SPR0)| // SPI Clock Rate + (0<<CPOL)| // Clock Polarity (0:SCK low / 1:SCK hi when idle) + (0<<CPHA)); // Clock Phase (0:leading / 1:trailing edge sampling) + + SPSR = (1<<SPI2X); // Double Clock Rate + + // SCK frequency 4MHz with above parameters. Deails in datasheet + +} + +void spi_transfer_sync (uint8_t * dataout, uint8_t * datain, uint8_t len) +// Shift full array through target device +{ + uint8_t i; + for (i = 0; i < len; i++) { + SPDR = dataout[i]; + while((SPSR & (1<<SPIF))==0); + datain[i] = SPDR; + } +} + +void spi_transmit_sync (uint8_t * dataout, uint8_t len) +// Shift full array to target device without receiving any byte +{ + uint8_t i; + for (i = 0; i < len; i++) { + SPDR = dataout[i]; + while((SPSR & (1<<SPIF))==0); + } +} + +uint8_t spi_fast_shift (uint8_t data) +// Clocks only one byte to target device and returns the received one +{ + SPDR = data; + while((SPSR & (1<<SPIF))==0); + return SPDR; +} + |
