UPD784026 Renesas Electronics Corporation., UPD784026 Datasheet - Page 688

• Manufacturer Part Number: UPD784026
• Description: 16/8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

(1) Read mode
(2) Output disable mode
(3) Standby mode
(4) Page data latch mode
(5) Page write mode
(6) Byte write mode
(7) Program verify mode
(8) Program inhibit mode
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Read mode is set by setting CE to L and OE to L.
If OE is set to H, data output becomes high impedance and the output disable mode is set.
Therefore, if multiple PD78P4026s are connected to the data bus, data can be read from any one device by controlling
the OE pin.
Setting CE to H sets the standby mode.
In this mode, data output becomes high-impedance irrespective of the status of OE.
Setting CE to H, PGM to H, and OE to L at the start of the page write mode sets the page data latch mode.
In this mode, 1-page 4-byte data is latched in the internal address/data latch circuit.
After 1-page 4-byte address and data are latched in the page data latch mode, a page write is executed by applying
a 0.1 ms program pulse (active-low) to the PGM pin while CE = H and OE = H. After this, program verification can
be performed by setting CE to L and OE to L.
If programming is not performed by one program pulse, repeated write and verify operations are executed X times
(X
A byte write is executed by applying a 0.1 ms program pulse (active-low) to the PGM pin while CE = L and OE = H.
After this, program verification can be performed by setting OE to L.
If programming is not performed by one program pulse, repeated write and verify operations are executed X times
(X
Setting CE to L, PGM to H, and OE to L sets the program verify mode.
After writing is performed, this mode should be used to check whether the data has been written correctly.
The program inhibit mode is used when the OE pins, V
in parallel, and you wish to write to one of these devices.
The page write mode or byte write mode described above is used to perform a write. At this time, a write is not performed
on devices on which the PGM pin is driven high.
10).
10).
CHAPTER 24
PD78P4026 PROGRAMMING
PP
pins and pins D0 to D7 of multiple PD78P4026s are connected