Datasheet

ATmega48/88/168 Automotive [DATASHEET]
7530K–AVR–07/14
62
10.3 Alternate Port Functions
Most port pins have alternate functions in addition to being general digital I/Os. Figure 10-5 shows how the port pin control
signals from the simplified Figure 10-2 on page 58 can be overridden by alternate functions. The overriding signals may not
be present in all port pins, but the figure serves as a generic description applicable to all port pins in the AVR
®
microcontroller family.
Figure 10-5. Alternate Port Functions
(1)
Note: 1. WRx, WPx, WDx, RRx, RPx, and RDx are common to all pins within the same port. clk
I/O
, SLEEP, and PUD
are common to all ports. All other signals are unique for each pin.
D
0
1
Q
WRx
RRx
WPx
PTOExn
Pxn
CLR
RESET
Synchronizer
DATA BUS
PORTxn
Q
0
1
Q
L
D
SET
CLR CLR
Q
QD
Q
PINxn
0
1
RESET
RPx
Pxn PULL-UP OVERRIDE ENABLE
Pxn PULL-UP OVERRIDE VALUE
PUD: PULL-UP DISABLEPUOExn:
Pxn PORT VALUE OVERRIDE VALUEPVOVxn:
Pxn PORT VALUE OVERRIDE ENABLEPVOExn:
Pxn DATA DIRECTION OVERRIDE ENABLE
Pxn DATA DIRECTION OVERRIDE VALUE
DDOExn:
DDOVxn:
SLEEP CONTROLSLEEP:
Pxn, PORT TOGGLE OVERRIDE ENABLEPTOExn:
Pxn DIGITAL INPUT ENABLE OVERRIDE VALUEDIEOVxn:
Pxn DIGITAL INPUT ENABLE OVERRIDE ENABLEDIEOExn:
I/O CLOCK
RDx:
RPx:
WRITE PINx
WRx:
ANALOG INPUT/OUTPUT PIN n ON PORTx
DIGITAL INPUT PIN n ON PORTx
RRx: READ PORTx REGISTER
WPx:
WRITE PORTx
AIOxn:
DIxn:
READ PORTx PIN
WDx:
READ DDRx
WRITE DDRxPUOVxn:
RDx
CLK
I/O
DIxn
AIOxn
CLK:
I/O
DIEOVxn
DIEOExn
PVOExn
DDOVxn
PVOVxn
0
1
PUOExn
PUOVxn
0
1
DDOExn
SLEEP
PUD
WDx
D
Q
CLR
DDxn
Q