HD6433308 Datasheet, PDF (255/349 Pages) Hitachi Semiconductor – Hitachi Single-Chip MicroComputer

Address in MCU mode
H'0000
Address in PROM mode
H'0000
On-chip
PROM
H'3FFF
H'3FFF
"1" output *
* ^{If this area is read in PROM mode,}
the output data are H'FF.
H'7FFF
Figure 13-3. Memory Map in PROM Mode
13.3 Programming
The write, verify, inhibited, and read sub-modes of the PROM mode are selected as shown in Table
13-4.
Table 13-4. Selection of Sub-Modes in PROM Mode
Pins
Sub-mode
CE
OE
VPP VCC EO7 – EO0
EA14 – EA0
Write
Low High VPP VCC Data input
Address input
Verify
High Low VPP VCC Data output
Address input
Programming inhibited High High VPP VCC High-impedance Address input
Note: The VPP and VCC pins must be held at the VPP and VCC voltage levels.
The H8/330 PROM uses the same, standard read/write specifications as the HN27C256 and
HN27256.
13.3.1 Writing and Verifying
An efficient, high-speed programming procedure can be used to write and verify PROM data. This
procedure writes data quickly without subjecting the chip to voltage stress and without sacrificing
data reliability. It leaves the data H’FF written in unused addresses.
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