SAB80C515A-5 Datasheet, PDF (59/108 Pages) Siemens Semiconductor Group – 8-Bit CMOS Single-Chip Microcontroller Family

SAB 80C515A/83C515A-5
Pin Definitions and Functions (cont’d)
Symbol Pin
Pin
Input (I) Function
P-LCC-68 P-MQFP-80 Output (O)
P6.7-P6.0 13-20
5-12
I
P3.0-P3.7 21-28
15-22
I/O
Port 6
is an 8-bit unidirectional input port to the A/
D converter. Port pins can be used for digital
input, if voltage levels simultaneously meet
the specifications high/low input voltages, and
for the eight multiplexed analog inputs.
Port 3
is an 8-bit bidirectional I/O port with internal
pullup resistors. Port 3 pins that have1's
written to them are pulled high by the internal
pullup resistors, and in that state can be used
as inputs. As inputs, port 3 pins being
externally pulled low will source current (I_IL, in
the DC characteristics) because of the internal
pullup resistors. Port 3 also contains the
interrupt, timer, serial port and external
memory strobe pins that are used by various
options. The output latch corresponding to a
secondary function must be programmed to a
one (1) for that function to operate. The
secondary functions are assigned to the pins
of port 3, as follows:
– R × D (P3.0): serial port’s receiver data
input (asynchronous) or data
input/output (synchronous)
– T × D (P3.1): serial port’s transmitter data
output (asynchronous) or
clock output (synchronous)
– INT0(P3.2): interrupt 0 input/timer 0 gate
control input
– INT1(P3.3): interrupt 1 input/timer 1 gate
control input
– T0 (P3.4): counter 0 input
– T1 (P3.5): counter 1 input
– WR(P3.6):
the write control signal
latches the data byte from
port 0 into the external data
memory
– RD(P3.7):
the read control signal
enables the external data
memory to port 0
Semiconductor Group
6-7