85
ATmega103(L)
0945G–09/01
• SS – Port B, Bit 0
SS: Slave port select input. When the SPI is enabled as a slave, this pin is configured as
an input regardless of the setting of DDB0. As a slave, the SPI is activated when this pin
is driven low. When the SPI is enabled as a master, the data direction of this pin is con-
trolled by DDB0. When the pin is forced to be an input, the pull-up can still be controlled
by the PORTB0 bit. See the description of the SPI port for further details.
Port B Schematics
Note that all port pins are synchronized. The synchronization latches are, however, not
shown in the figures.
Figure 54.
Port B Schematic Diagram (Pin PB0)