Datasheet

Table Of Contents
85
ATmega640/V-1280/V-1281/V-2560/V-2561/V [DATASHEET]
2549Q–AVR–02/2014
13.3.6 Alternate Functions of Port F
The Port F has an alternate function as analog input for the ADC as shown in Table 13-18. If some Port F pins are
configured as outputs, it is essential that these do not switch when a conversion is in progress. This might corrupt
the result of the conversion. If the JTAG interface is enabled, the pull-up resistors on pins PF7(TDI), PF5(TMS),
and PF4(TCK) will be activated even if a Reset occurs.
TDI, ADC7 – Port F, Bit 7
ADC7, Analog to Digital Converter, Channel 7.
TDI, JTAG Test Data In: Serial input data to be shifted in to the Instruction Register or Data Register (scan chains).
When the JTAG interface is enabled, this pin can not be used as an I/O pin.
TDO, ADC6 – Port F, Bit 6
ADC6, Analog to Digital Converter, Channel 6.
TDO, JTAG Test Data Out: Serial output data from Instruction Register or Data Register. When the JTAG interface
is enabled, this pin can not be used as an I/O pin.
The TDO pin is tri-stated unless TAP states that shift out data are entered.
TMS, ADC5 – Port F, Bit 5
ADC5, Analog to Digital Converter, Channel 5.
TMS, JTAG Test Mode Select: This pin is used for navigating through the TAP-controller state machine. When the
JTAG interface is enabled, this pin can not be used as an I/O pin.
TCK, ADC4 – Port F, Bit 4
ADC4, Analog to Digital Converter, Channel 4.
TCK, JTAG Test Clock: JTAG operation is synchronous to TCK. When the JTAG interface is enabled, this pin can
not be used as an I/O pin.
ADC3 – ADC0 – Port F, Bit 3:0
Analog to Digital Converter, Channel 3:0.
Table 13-18. Port F Pins Alternate Functions
Port Pin Alternate Function
PF7 ADC7/TDI (ADC input channel 7 or JTAG Test Data Input)
PF6 ADC6/TDO (ADC input channel 6 or JTAG Test Data Output)
PF5 ADC5/TMS (ADC input channel 5 or JTAG Test Mode Select)
PF4 ADC4/TCK (ADC input channel 4 or JTAG Test ClocK)
PF3 ADC3 (ADC input channel 3)
PF2 ADC2 (ADC input channel 2)
PF1 ADC1 (ADC input channel 1)
PF0 ADC0 (ADC input channel 0)