ATTINY20-MMHR Atmel, ATTINY20-MMHR Datasheet - Page 132

• Manufacturer Part Number: ATTINY20-MMHR
• Description: MCU AVR 2KB FLASH 12MHZ 20QFN
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY20-MMHR

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 12MHz
• Connectivity: I²C, SPI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 12
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

132
ATtiny20
Note:
The following code examples show how to initialize the SPI as a Slave and how to perform a
simple reception.
C Code Example
Assembly Code Example
void SPI_MasterInit(void)
{
}
void SPI_MasterTransmit(char cData)
{
}
SPI_SlaveInit:
SPI_SlaveReceive:
/* 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);
/* Start transmission */
SPDR = cData;
/* Wait for transmission complete */
while(!(SPSR & (1<<SPIF)))
; Set MISO output, all others input
ldi
out
; Enable SPI
ldi
out
ret
; Wait for reception complete
in
sbrs r16, SPIF
rjmp SPI_SlaveReceive
; Read received data and return
in
ret
See ”Code Examples” on page 6.
;
r17,(1<<DD_MISO)
DDR_SPI,r17
r17,(1<<SPE)
SPCR,r17
r16, SPSR
r16,SPDR
8235B–AVR–04/11