Datasheet

Table 23-4. CPHA Functionality
CPHA Leading Edge Trailing Edge
0 Sample Setup
1 Setup Sample
Bits 1:0 – SPRn[1:0] SPI Clock Rate Select [n = 1:0]
These two bits control the SCK rate of the device configured as a Master. SPR1 and SPR0 have no effect
on the Slave. The relationship between SCK and the Oscillator Clock frequency f
osc
is shown in the table
below.
Table 23-5. Relationship between SCK and Oscillator Frequency
SPI2X SPR1 SPR0 SCK Frequency
0 0 0 f
osc
/4
0 0 1 f
osc
/16
0 1 0 f
osc
/64
0 1 1 f
osc
/128
1 0 0 f
osc
/2
1 0 1 f
osc
/8
1 1 0 f
osc
/32
1 1 1 f
osc
/64
AVR 8-Bit Microcontroller
SPI – Serial Peripheral Interface
© 2017 Microchip Technology Inc.
Datasheet Complete
40001974A-page 180