atmega103 ATMEL Corporation, atmega103 Datasheet - Page 90

• Manufacturer Part Number: atmega103
• Description: Atmega103 8-bit With 128k Bytes Of In-system Programmable Flash
• Manufacturer: ATMEL Corporation

DDB1. When the pin is forced to be an input, the pull-up can still be controlled by the
PORTB1 bit. See the description of the SPI port for further details.
• 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
controlled by DDB0. When the pin is forced to be an input, the pull-up can still be con-
trolled 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)
ATmega103(L)
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