UPD75P216ACW NEC, UPD75P216ACW Datasheet - Page 11

• Manufacturer Part Number: UPD75P216ACW
• Description: 4-BIT SINGLE-CHIP MICROCOMPUTER
• Manufacturer: NEC

3.2 PROM WRITE PROCEDURE
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10) Perform one additional write (duration of 1ms
(11) Select the program inhibit mode.
(12) Apply four pulses to the X1 pin to increment the program memory address by one.
(13) Repeat steps (7) to (12) until the end address is reached.
(14) Select the zero clear program memory address mode.
(15) Return the V
(16) Turn off the power.
P40-P43
P50-P53
V
V
DD
V
PROM can be written at high speed using the following procedure: (see the following figure)
PP
(P30)
(P31)
(P32)
(P33)
MD0
MD1
MD2
MD3
DD
V
V
V
Pull unused pins to V
Supply 5 volts to the V
Wait for 10 s.
Select the zero clear program memory address mode.
Supply 6 volts to the V
Select the program inhibit mode.
Write data in the 1 ms write mode.
Select the program inhibit mode.
Select the verify mode. If the data is correct, proceed to step (10). If not repeat steps (7), (8) and (9).
+1
X1
DD
DD
PP
DD
and V
Input data
PP
SS
Write
DD
DD
pins back to + 5 volts.
through resistors. Set the X1 pin low.
and V
and 12.5 volts to the V
Fig. 3-1
X repetition
PP
pins.
Timing of Program Memory Write
Verify
Output
data
PP
number of writes at (7) to (9)).
pins.
Additional write
Input data
increment
Address
PD75P216A
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