Datasheet

170
7593L–AVR–09/12
AT90USB64/128
Note: 1. See “Alternate functions of Port B” on page 79 for a detailed description of how to define the
direction of the user defined SPI pins.
The following code examples show how to initialize the SPI as a Master and how to perform a
simple transmission. DDR_SPI in the examples must be replaced by the actual Data Direction
Register controlling the SPI pins. DD_MOSI, DD_MISO and DD_SCK must be replaced by the
actual data direction bits for these pins. For example, if MOSI is placed on pin PB5, replace
DD_MOSI with DDB5 and DDR_SPI with DDRB.
Table 18-1. SPI pin overrides
(1)
.
Pin Direction, master SPI Direction, slave SPI
MOSI User defined Input
MISO Input User defined
SCK User defined Input
SS User defined Input