ATTINY48PRE Datasheet, PDF (121/298 Pages) ATMEL Corporation – 123 Powerful Instructions – Most Single Clock Cycle Execution

ATtiny48/88
C Code Example⁽¹⁾
void SPI_MasterInit(void)
{
/* Set MOSI and SCK output, all others input */
DDR_SPI = (1<<DD_MOSI)|(1<<DD_SCK);
/* Enable SPI, Master, set clock rate fck/16 */
SPCR = (1<<SPE)|(1<<MSTR)|(1<<SPR0);
}
void SPI_MasterTransmit(char cData)
{
/* Start transmission */
SPDR = cData;
/* Wait for transmission complete */
while(!(SPSR & (1<<SPIF)))
;
}
Note: 1. See ”About Code Examples” on page 7.
The following code examples show how to initialize the SPI as a Slave and how to perform a
simple reception.
Assembly Code Example⁽¹⁾
SPI_SlaveInit:
; Set MISO output, all others input
ldi r17,(1<<DD_MISO)
out DDR_SPI,r17
; Enable SPI
ldi r17,(1<<SPE)
out SPCR,r17
ret
SPI_SlaveReceive:
; Wait for reception complete
sbis SPSR,SPIF
rjmp SPI_SlaveReceive
; Read received data and return
in r16,SPDR
ret
Note: 1. See ”About Code Examples” on page 7.
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