Operating Modes When Writing To And Verifying The Program Memory; Writing To The Program Memory - NEC PD750004 User Manual

µPD75008 USER'S MANUAL
9.1

OPERATING MODES WHEN WRITING TO AND VERIFYING THE PROGRAM MEMORY

If +6 V is applied to the V
memory write/verify mode. The specific operating mode is then selected by the setting of the MD0 through
MD3 pins as listed in the table below.
Operating mode specification
V V
PP DD
+12.5 V +6 V
Remark X indicates L or H.

9.2 WRITING TO THE PROGRAM MEMORY

The procedure for writing to program memory is described below; high-speed write is possible.
(1) Pull low all unused pins to V
Bring X1 to low level.
(2) Apply 5 V to V
DD
(3) Wait 10 µs.
(4) Select program memory address clear mode.
(5) Apply 6 V to V
DD
(6) Select program inhibit mode.
(7) Select write mode for 1 ms duration and write data.
(8) Select program inhibit mode.
(9) Select verify mode. If write is successful, proceed to step (10). If write fails, repeat steps (7) to (9).
(10) Perform additional write for (Number of repetitions of steps (7) to (9)) x 1 ms duration.
(11) Select program inhibit mode.
(12) Increment the program memory address by inputting four pulses on the X1 pin.
(13) Repeat steps (7) to (12) until the last address is reached.
(14) Select program memory address clear mode.
(15) Apply 5 V to V
DD
(16) Turn the power off.
230
pin and +12.5 V is applied to the V
DD
MD0 MD1 MD2
H L H
L H H
L L H
H X H
by means of resistors.
SS
and to V .
PP
and 12.5 V to V .
PP
and to V .
PP
pin, the µPD75P0016 enters program
PP
MD3
L Program memory address clear mode
H Write mode
H Verify mode
H Program inhibit mode
Operating mode