Atmel AVR AT90CAN128, Manual

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78
7679H–CAN–08/08
AT90CAN32/64/128
9.3.4 Alternate Functions of Port C
The Port C has an alternate function as the address high byte for the External Memory Interface.
The Port C pins with alternate functions are shown in Table 9-9 .
The alternate pin configuration is as follows:
• A15/CLKO – Port C, Bit 7
A15, External memory interface address 15.
CLKO, Divided System Clock: The divided system clock can be output on the PC7 pin. The
divided system clock will be output if the CKOUT Fuse is programmed, regardless of the
PORTC7 and DDC7 settings. It will also be output during reset.
Table 9-8. Overriding Signals for Alternate Functions in PB3..PB0
Signal Name PB3/MISO PB2/MOSI PB1/SCK PB0/SS
PUOE SPE • MSTR SPE • MSTR SPE • MSTR SPE • MSTR
PUOV PORTB3 • PUD PORTB2 • PUD PORTB1 • PUD PORTB0 • PUD
DDOE SPE • MSTR SPE • MSTR SPE • MSTR SPE • MSTR
DDOV 0 0 0 0
PVOE SPE • MSTR SPE • MSTR SPE • MSTR 0
PVOV
SPI SLAVE
OUTPUT SPI MASTER
OUTPUT
SCK OUTPUT 0
PTOE 0 0 0 0
DIEOE 0 0 0 0
DIEOV 0 0 0 0
DI
SPI MASTER
INPUT SPI SLAVE
INPUT
• RESET
SCK INPUT SPI SS
AIO – – – –
Table 9-9. Port C Pins Alternate Functions
Port Pin Alternate Function
PC7
A15/CLKO (External memory interface address 15 or Divided System
Clock)
PC6 A14 (External memory interface address 14)
PC5 A13 (External memory interface address 13)
PC4 A12 (External memory interface address 12)
PC3 A11 (External memory interface address 11)
PC2 A10 (External memory interface address 10)
PC1 A9 (External memory interface address 9)
PC0 A8 (External memory interface address 8)