2 prom programming mode pins (upd78p078 only) – NEC uPD78P078 User Manual
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69
CHAPTER 3 PIN FUNCTION (
µ
PD78078 SUBSERIES)
(2) Non-port pins (2/2)
Pin Name
Input/Output
Function
After Reset Alternate Function
AD0 to AD7
Input/Output
Low-order address/data bus when expanding external memory
Input
P40 to P47
A0 to A7
Output
Low-order address bus when expanding external memory
Input
P80 to P87
A8 to A15
Output
High-order address bus when expanding external memory
Input
P50 to P57
RD
Strobe signal output for read operation from external memory
P64
WR
Strobe signal output for write operation to external memory
P65
WAIT
Input
Wait insertion when accessing external memory
Input
P66
Strobe output externally latching address information output to ports 4,
5 to access external memory
ANI0 to ANI7
Input
A/D converter analog input
Input
P10 to P17
ANO0, ANO1
Output
D/A converter analog output
Input
P130, P131
AV
REF0
Input
A/D converter reference voltage input
—
—
AV
REF1
Input
D/A converter reference voltage input
—
—
AV
DD
—
A/D converter analog power supply. Connect to V
DD
.
—
—
AV
SS
—
A/D converter, D/A converter ground potential. Connect to V
SS
.
—
—
RESET
Input
System reset input
—
—
X1
Input
—
—
X2
—
—
—
XT1
Input
Input
P07
XT2
—
—
—
V
DD
—
Positive power supply
—
—
High-voltage application for program write/verify. Connect directly to
V
SS
in normal operating mode.
V
SS
—
Ground potential
—
—
IC
—
Internally connected. Connect directly to V
SS.
—
—
3.1.2 PROM programming mode pins (
µ
PD78P078 only)
Pin Name
Input/Output
Function
PROM programming mode setting.
RESET
Input
When +5 V or +12.5 V is applied to the V
PP
pin or a low level voltage is applied to the RESET pin,
the PROM programming mode is set.
V
PP
Input
High-voltage application for PROM programming mode setting and program write/verify.
A0 to A16
Input
Address bus
D0 to D7
Input/output Data bus
CE
Input
PROM enable input/program pulse input
OE
Input
Read strobe input to PROM
PGM
Input
Program/program inhibit input in PROM programming mode
V
DD
—
Positive power supply
V
SS
—
Ground potential
Output
Input
ASTB
Output
Input
P67
V
PP
—
—
—
Crystal connection for main system clock oscillation
Crystal connection for subsystem clock oscillation