sak-c868p-1rr Infineon Technologies Corporation, sak-c868p-1rr Datasheet - Page 45

• Manufacturer Part Number: sak-c868p-1rr
• Description: 8 - Bit Cmos Microcontroller
• Manufacturer: Infineon Technologies Corporation

4
This chapter gives detailed information about all on-chip peripherals of the C868 except
for the integrated interrupt controller, which is described separately in chapter 7.
4.1
The C868 BA has two kinds of ports. The first kind is push-pull ports instead of the
traditional quasi-bidirectional ports. The ports belonging to this kind is part of port 1 which
is a 5-bit I/O port and port 3 which is an eight-bit I/O port. When configured as inputs,
these ports will be high impedance with Schmitt trigger feature. Port 3 is alternate for
capture/compare functions whereas, port 1 has alternate functions for some of the pins.
The second kind is dedicated ports which are shared by the some port 1 input, interrupts,
timer 2 inputs, capture/compare hall inputs and analog inputs.
4.2
The I/O part of port 1 and 3 are push-pull ports. Port 1 and port 3 can function as normal
I/O ports which have associated SFRs at address 90
ports also have alternate functions as listed in
There are three SFRs dedicated for each of these ports. The first one is the port latch
(P1/P3) and second one is direction control register (P1DIR/P3DIR) which is used to set
the direction for each pin. In P1DIR/P3DIR, if the bit is set to 0 the respective port pin is
an output, and 1 means an input. For P1.5-7, when set to output, it is internally
connected to the CCU module. After reset, by default all the Port 1 and 3 pins are input.
The third one is the alternate function register (P1ALT/P3ALT) which is used to set the
function of each pin. When used as alternate function, the direction of the pins has to be
set accordingly.
When the bit is set an input, any read operation will return the value at the port. When
the bit is set as an output, a read operation will return the latched value if it is part of a
read-modify-write operation, otherwise a read operation will return the value at the port.
Note: While in the idle mode or the power down mode the I/O ports hold the last values.
User’s Manual
On-Chip Peripheral Components
Ports
I/O Ports
4-1
Table
On-Chip Peripheral Components
4-2.
H
and B0
H
respectively. These
V 1.0, 2003-01
C868