NEC PD75P308 Personal Computer User Manual


 
µ
PD75P308
5
E-B
P00 Input INT4
P01 Input/Output SCK
P02 Input/Output SO/SB0
P03 Input/Output SI/SBI
P10 INT0
P11 INT1
P12 INT2
P13 TI0
P20 PTO0
P21
P22 PCL
P23 BUZ
P30*
2
P31*
2
P32*
2
MD2
P33*
2
MD3
P40-43*
2
Input/Output
P50-P53*
2
Input/Output
P60 KR0
P61 KR1
P62 KR2
P63 KR3
P70 KR4
P71 KR5
P72 KR6
P73 KR7
BP0 S24
BP1 S25
BP2 S26
BP3 S27
BP4 S28
BP5 S29
BP6 S30
BP7 S31
1. PIN FUNCTIONS
1.1 PORT PINS
4-bit input port (PORT0)
Pull-up resistors can be specified in 3-bit
units for the P01 to P03 pins by software.
Input
Input/
Output
Circuit
TYPE
*1
Pin Name
Input/Output Function 8-Bit I/O When Reset
Also Served
As
F -A
F -B
B
M -C
Input
X
InputX
4-bit input/output port (PORT2)
Internal pull-up resistors can be
specified in 4-bit units by software.
Input
X
E-B
Input
X
MD0LCDCL
SYNC
MD1
M-A
M-A
High impedance
High impedance
4-bit input/output port (PORT7)
Internal pull-up resistors can be
specified in 4-bit units by software.
Input
Input
1-bit output port (BIT PORT)
Shared with a segment output pin.
G-C
*3
X
F -A
F -A
Input/Output
Input/Output
Output
Output
Input/Output
Input/Output
With noise elimination function
4-bit input port (PORT1)
Internal pull-up resistors can be
specified in 4-bit units by software.
Programmable 4-bit input/output port
(PORT3)
This port can be specified for input/output
in bit units.
Internal pull-up resistors can be
specified in 4-bit units by software.
N-ch open-drain 4-bit input/output port
(PORT4)
Data input/output pin for writing and
verifying of program memory (PROM)
(lower 4 bits)
N-ch open-drain 4-bit input/output port
(PORT5)
Data input/output pin for writing and
verifying of program memory (PROM)
(upper 4 bits)
Programmable 4-bit input/output port
(PORT6)
This port can be specified for input/output
in bit units.
Internal pull-up resistors can be specified
in 4-bit units by software.
*1: Circles indicate schmitt trigger inputs.
2: Can directly drive LED.
3: For BP0-7, V
LC1 indicated below are selected as the input source.
However, the output level is changed depending on BP0-7 and the VLC1 external circuits.
B -C