ATmega32A Datasheet - Sunrom Technologies

ATmega32ATable 12-2.Generic Description of Overriding Signals for Alternate FunctionsSignal Name Full Name DescriptionPUOEPull-up OverrideEnableIf this signal is set, the pull-up enable is controlled by thePUOV signal. If this signal is cleared, the pull-up is enabledwhen {DDxn, PORTxn, PUD} = 0b010.PUOV Pull-up Override Value If PUOE is set, the pull-up is enabled/disabled when PUOVis set/cleared, regardless of the setting of the DDxn,PORTxn, and PUD Register bits.DDOEDDOVPVOEPVOVDIEOEDIEOVData DirectionOverride EnableData DirectionOverride ValuePort Value OverrideEnablePort Value OverrideValueDigital Input EnableOverride EnableDigital Input EnableOverride ValueIf this signal is set, the Output Driver Enable is controlled bythe DDOV signal. If this signal is cleared, the Output driveris enabled by the DDxn Register bit.If DDOE is set, the Output Driver is enabled/disabled whenDDOV is set/cleared, regardless of the setting of the DDxnRegister bit.If this signal is set and the Output Driver is enabled, the portvalue is controlled by the PVOV signal. If PVOE is cleared,and the Output Driver is enabled, the port Value iscontrolled by the PORTxn Register bit.If PVOE is set, the port value is set to PVOV, regardless ofthe setting of the PORTxn Register bit.If this bit is set, the Digital Input Enable is controlled by theDIEOV signal. If this signal is cleared, the Digital InputEnable is determined by MCU-state (Normal Mode, sleepmodes).If DIEOE is set, the Digital Input is enabled/disabled whenDIEOV is set/cleared, regardless of the MCU state (NormalMode, sleep modes).DI Digital Input This is the Digital Input to alternate functions. In the figure,the signal is connected to the output of the schmitt triggerbut before the synchronizer. Unless the Digital Input is usedas a clock source, the module with the alternate function willuse its own synchronizer.AIO Analog Input/ output This is the Analog Input/output to/from alternate functions.The signal is connected directly to the pad, and can be usedbi-directionally.The following subsections shortly describe the alternate functions for each port, and relate theoverriding signals to the alternate function. Refer to the alternate function description for furtherdetails.12.3.1 Alternate Functions of Port APort A has an alternate function as analog input for the ADC as shown in Table 12-3. If somePort A pins are configured as outputs, it is essential that these do not switch when a conversionis in progress. This might corrupt the result of the conversion.8155C–AVR–02/1157