HD6433832S Datasheet, PDF (128/560 Pages) Renesas Technology Corp – single-chip microcomputers

6.3 H8/3834 Programming
The write, verify, and other modes are selected as shown in table 6.3 in H8/3834 PROM mode.
Table 6.3 Mode Selection in H8/3834 PROM Mode
Pin
Mode
CE OE V_PP
V_CC
EO₇ to EO₀
EA₁₄ to EA₀
Write
L
H
V_PP
V_CC
Data input
Address input
Verify
H
L
V_PP
V_CC
Data output
Address input
Programming disabled H
H
V_PP
V_CC
High impedance Address input
Notation:
L: Low level
H: High level
V_PP: V_PP level
V_CC: V_CC level
The specifications for writing and reading the on-chip PROM are identical to those for the
standard HN27C256 EPROM.
6.3.1 Writing and Verifying
An efficient, high-performance programming method is available for writing and verifying the
PROM data. This method achieves high speed without voltage stress on the device and without
lowering the reliability of written data. H'FF data is written in unused address areas.
The basic flow of this high-performance programming method is shown in figure 6.4. Table 6.4
and table 6.5 give the electrical characteristics in programming mode. Figure 6.5 shows a
write/verify timing diagram.
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