µ
PD754144, 754244
19
Data Sheet U10040EJ2V1DS
7. PERIPHERAL HARDWARE FUNCTIONS
7.1 Digital Input/Output Ports
The following two types of I/O ports are provided.
•
CMOS input (Port 7)
:
4
•
CMOS I/O (Ports 3, 6, 8)
:
9
Total
: 13
Table 7-1. Types and Features of Digital Ports
Port Name
Function
Operation and Features
Remarks
PORT3
4-bit I/O
Can be set to input or output mode bit-wise.
Also used as PTO0 to PTO2 pins.
PORT6
Also used as AV
REF
, INT0, PTH00,
and PTH01 pins.
PORT7
4-bit input
4-bit input only port
Also used as KR4 to KR7 pins.
On-chip pull-up resistor connection can be specified
by mask option bit-wise.
PORT8
1-bit I/O
Can be set to input or output mode bit wise.
_
7.2 Clock Generator
The clock generator provides the clock signals to the CPU and peripheral hardware. Its configuration is shown
in Figures 7-1 and 7-2.
The operation of the clock generator is set with the processor clock control register (PCC).
The instruction execution time can be changed.
•
µ
PD754144
•
4, 8, 16, 64
µ
s (when the system clock f
CC
operates at 1.0 MHz)
•
µ
PD754244
•
0.95, 1.91, 3.81, 15.3
µ
s (when the system clock f
X
operates at 4.19 MHz)
•
0.67, 1.33, 2.67, 10.7
µ
s (when the system clock f
X
operates at 6.0 MHz)
*
