UPD753108 Datasheet, PDF (30/459 Pages) NEC – 4-bit Single-chip Microcontrollers

CHAPTER 2 PIN FUNCTION
Table 2-2. Pin Function of Pins Other Than Port Pins (2/2)
Pin Name
BIAS
LCDCL^{Note 3}
SYNC^{Note 3}
X1
Input/Output
Alternate
Function
Output
—
Output P30
Output P31
Input
—
X2
—
XT1
Input
—
XT2
—
Function
I/O Circuit
After Reset _{TypeNote 1}
Output for external split resistor disconnect
Note 2
—
Clock output for externally expanded driver
Input
E-B
Clock output for externally expanded driver sync Input
E-B
Crystal/ceramic connection pin for the main
—
—
system clock oscillator. When inputting the
external clock, input the external clock to pin
X1, and the reverse phase of the external
clock to pin X2.
Crystal connection pin for the subsystem
—
—
clock oscillator. When the external clock is
used, input the external clock to pin XT1. In
this case, input the reverse phase of clock to
pin XT2. Pin XT1 can be used as a 1-bit
input (test) pin.
RESET
MD0 to MD3
Input
Input
—
P30 to P33
D0 to D3
D4 to D7
IC
VPP
Input/Output P60/KR0 to
P63/KR3
P50 to P53
—
—
—
—
VDD
—
—
VSS
—
—
System reset input (low-level active)
Provided only to the µPD75P3116.
Select modes for writing/verifying program
memory (PROM).
Provided only to the µPD75P3116.
Data bus pins during program memory
(PROM) write/verify.
Internally connected. Connect this pin
directly to VDD.
Provided only to the µPD75P3116.
Supplies voltage necessary for writing/
verifying program memory (PROM).
Directly connect this pin to VDD for normal
operation.
Apply +12.5 V to this pin to write/verify
PROM.
Positive power supply
Ground potential
—
Input
Input
High-
impedance
—
—
—
—
[B]
E-B
[F]-A
M-E
—
—
—
—
Notes 1. The circuit types enclosed with [ ] are Schmitt-triggered input circuits.
2. When a split resistor is contained .......... Low level
When no split resistor is contained ........ High-impedance
3. These pins are provided for future system expansion. At present, these pins are used only as pins
P30 and P31.
30