SAB80C517 Datasheet, PDF (14/61 Pages) Siemens Semiconductor Group – 8-Bit CMOS Single-Chip Microcontroller

SAB 80C517/80C537
Pin Definitions and Functions (cont’d)
Symbol
Pin Number
I/O ^*) Function
P-LCC-84 P-MQFP-100-2
P6.0 - P6.7 70 - 77
46 - 50,
54 - 56
P8.0 - P8.3 78 - 81
57 - 60
* _{I = Input}
O = Output
I/O Port 6
is a bidirectional I/O port with internal
pull-up resistors. Port 6 pins that have
1 s written to them are pulled high by
the internal pull-up resistors, and in that
state can be used as inputs. As inputs,
port 6 pins being externally pulled low
will source current (I_IL, in the
DC characteristics) because of the
internal pull-up resistors. Port 6 also
contains the external A/D converter
control pin and the transmit and receive
pins for serial channel 1. 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 6, as follows:
– ADST (P6.0): external A/D converter
start pin
– R × D1 (P6.1): receiver data input of
serial interface 1
– T × D1 (P6.2): transmitter data output
of serial interface 1
I
Port 8
is a 4-bit unidirectional input port. Port
pins can be used for digital input, if
voltage levels meet the specified input
high/low voltages, and for the higher
4-bit of the multiplexed analog inputs of
the A/D converter, simultaneously
Semiconductor Group
13