ATmega16(L)
Table 30.
Overriding Signals for Alternate Functions in PC3..PC0
Signal
Name
PUOE
PUOV
DDOE
DDOV
PVOE
PVOV
DIEOE
DIEOV
DI
AIO
Note:
PC3/TMS
JTAGEN
1
JTAGEN
0
0
0
JTAGEN
0
–
PC2/TCK
JTAGEN
1
JTAGEN
0
0
0
JTAGEN
0
–
PC1/SDA
TWEN
PORTC1 • PUD
TWEN
SDA_OUT
TWEN
0
0
0
–
PC0/SCL
TWEN
PORTC0 • PUD
TWEN
SCL_OUT
TWEN
0
0
0
–
TMS
TCK
SDA INPUT
SCL INPUT
1. When enabled, the Two-wire Serial Interface enables slew-rate controls on the output pins
PC0 and PC1. This is not shown in the figure. In addition, spike filters are connected between
the AIO outputs shown in the port figure and the digital logic of the TWI module.
Alternate Functions of
Port D
The Port D pins with alternate functions are shown in
Table 31.
Port D Pins Alternate Functions
Port Pin
PD7
PD6
PD5
PD4
PD3
PD2
PD1
PD0
Alternate Function
OC2 (Timer/Counter2 Output Compare Match Output)
ICP1 (Timer/Counter1 Input Capture Pin)
OC1A (Timer/Counter1 Output Compare A Match Output)
OC1B (Timer/Counter1 Output Compare B Match Output)
INT1 (External Interrupt 1 Input)
INT0 (External Interrupt 0 Input)
TXD (USART Output Pin)
RXD (USART Input Pin)
The alternate pin configuration is as follows:
• OC2 – Port D, Bit 7
OC2, Timer/Counter2 Output Compare Match output: The PD7 pin can serve as an external out-
put for the Timer/Counter2 Output Compare. The pin has to be configured as an output (DDD7
set (one)) to serve this function. The OC2 pin is also the output pin for the PWM mode timer
function.
• ICP1 – Port D, Bit 6
ICP1 – Input Capture Pin: The PD6 pin can act as an Input Capture pin for Timer/Counter1.
63
2466S–AVR–05/09
ATMEL [ ATMEL CORPORATION ]
