Table of Contents
Advertisement
Downloaded from
Elcodis.com
electronic components distributor
14.3 Programming
Table 14-3 indicates how to select the program, verify, and other modes in PROM mode.
Table 14-3 Mode Selection in PROM Mode
CE
OE
Mode
Program
L
H
Verify
L
L
Program inhibited
L
L
L
H
H
L
H
H
Legend
L:
Low voltage level
H:
High voltage level
V
: V
voltage level
PP
PP
V
: V
voltage level
CC
CC
Read/write specifications are the same as for the standard HN27C101 EPROM, except that page
programming is not supported. Do not select page programming mode. A PROM programmer that
supports only page-programming mode cannot be used. When selecting a PROM programmer,
check that it supports a byte-at-a-time high-speed programming mode. Be sure to set the address
range to H'0000 to H'FFFF.
14.3.1 Programming and Verification
An efficient, high-speed programming procedure can be used to program and verify PROM data.
This procedure programs the chip quickly without subjecting it to voltage stress and without
sacrificing data reliability. Unused address areas contain H'FF data. Figure 14-4 shows the basic
high-speed programming flowchart. Tables 14-4 and 14-5 list the electrical characteristics of the
chip during programming. Figure 14-5 shows a timing chart.
Pins
PGM
V
V
EO
PP
CC
7
L
V
V
Data input
PP
CC
H
V
V
Data output
PP
CC
L
V
V
High impedance
PP
CC
H
L
H
397
to EO
EA
to EA
0
16
0
Address input
Address input
Address input
Advertisement
Table of Contents
