SAB80C515A-5 Datasheet, PDF (58/108 Pages) Siemens Semiconductor Group – 8-Bit CMOS Single-Chip Microcontroller Family

SAB 80C515A/83C515A-5
Pin Definitions and Functions
Symbol Pin
Pin
Input (I) Function
P-LCC-68 P-MQFP-80 Output (O)
P4.0-P4.7 1-3, 5-9 72-74,
I/O
76-80
Port 4
is an 8-bit bidirectional I/O port with internal
pull-up resistors. Port 4 pins that have 1’s writ-
ten to them are pulled high by the internal pull-
up resistors, and in that state can be used as
inputs. As inputs, port 4 pins being externally
pulled low will source current (I _IL, in the DC
characteristics) because of the internal pull-up
resistors.
P4 also contains the external A/D converter
control pin. The output latch corresponding to
a secondary function must be programmed to
a one (1) for that function to operate. The sec-
ondary function assigned to port 6:
– ADST(P4.0): external A/D converter start
pin
PE/SWD 4
75
I
Power saving mode enable/Start Watch-
dog Timer
A low level on this pin allows the software to
enter the power down, idle and slow down
mode. In case the low level is also seen during
reset, the watchdog timer function is off on de-
fault.
Use of the software controlled power saving
modes is blocked, when this pin is held on
high level. A high level during reset performs
an automatic start of the watchdog timer im-
mediately after reset.
When left unconnected this pin is pulled high
by a weak internal pull-up resistor.
RESET 10
1
V _AREF1
11
3
V_AGND
12
4
I
Reset pin
A low level on this pin for the duration of two
machine cycles while the oscillator is running
resets the SAB 80C515A. A small internal
pullup resistor permits power-on reset using
only a capacitor connected to V _SS
Reference voltage for the A/D converter
Reference ground for the A/D converter
Semiconductor Group
6-6