UPD78P4916 Datasheet, PDF (22/56 Pages) NEC – 16-BIT SINGLE-CHIP MICROCONTROLLER

µPD78P4916
(1) Read mode
By setting CE = L and OE = L, the device enters the read mode.
(2) Output disable mode
By setting OE = H, the device enters the output disable mode, where data output pins go to high impedance
state.
Therefore it is possible to read data from a specified device by enabling only the OE pin of the device to be
read, if two or more µPD78P4916s are connected to a data bus.
(3) Standby mode
By setting CE = H, the device enters the Standby mode.
In this mode, data output pins go to high impedance state regardless of the OE pin condition.
(4) Page data latch mode
By setting CE = H, PGM = H, and OE = L at the beginning of page programming mode, the device enters the
page data latch mode.
In this mode, 4-byte data are latched in page units (consisting of 4 bytes) to internal address/data latch circuit.
(5) Page programming mode
After one-page data (consisting of 4 bytes) and their address are latched in the page data latch mode, the page
programming operation is executed by applying 0.1-ms programming pulse (active low) to the PGM pin under
CE = H, OE = H conditions. Following that operation, the programming data is verified by setting CE = L and
OE = L.
When data is not programmed by one programming pulse, the write and verify operations are repeated X times
(X ≤ 10).
(6) Byte programming mode
Applying 0.1-ms programming pulse (active low) to the PGM pin under CE = L and OE = H condition, byte
programming operation is executed. Next, the programming data is verified by setting OE = L.
When data is not programmed by one programming pulse, the write and verify operations are repeated X times
(X ≤ 10).
(7) Program verify mode
By setting CE = L, PGM = H, and OE = L, the device enters the program verify mode. Check whether data
is programmed correctly or not in this mode after write operation.
(8) Program inhibit mode
When the OE pins, VPP pins, and D0-D7 pins of two or more µPD78P4916s are connected in parallel, use
program inhibit mode to write data to one of those devices.
Programming is executed in the page programming mode or byte programming mode as mentioned above. At
that time, data is not programmed to a device for which high level voltage is applied to the PGM pin.
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