High-Performance SAB 80C517A/83C517A-5 8-Bit CMOS Single ...

SAB 80C517A/83C517A-5Pin Definitions and FunctionsSymbol Pin Number I/O *) FunctionP-LCC-84P-MQFP-100-2P4.0 – P4.7 1– 3, 5 – 9 64 - 66,68 - 72I/O Port 4is a bidirectional I/O port with internalpull-up resistors. Port 4 pins that have 1s written to them are pulled high by theinternal pull-up resistors, and in thatstate can be used as inputs. As inputs,port 4 pins being externally pulled lowwill source current (I IL, in the DC characteristics)because of the internal pullupresistors.This port also serves alternate comparefunctions. The secondary functions areassigned to the pins of port 4 as follows:– CM0 (P4.0): Compare Channel 0– CM1 (P4.1): Compare Channel 1– CM2 (P4.2): Compare Channel 2– CM3 (P4.3): Compare Channel 3– CM4 (P4.4): Compare Channel 4– CM5 (P4.5): Compare Channel 5– CM6 (P4.6): Compare Channel 6– CM7 (P4.7): Compare Channel 7PE/SWD 4 67 I Power saving modes enable StartWatchdog TimerA low level on this pin allows the softwareto enter the power down, idle andslow down mode. In case the low levelis also seen during reset, the watchdogtimer function is off on default.Use of the software controlled powersaving modes is blocked, when this pinis held on high level. A high level duringreset performs an automatic start of thewatchdog timer immediately after reset.When left unconnected this pin is pulledhigh by a weak internal pull-up resistor.* I = InputO = OutputSemiconductor Group 7