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MOTOROLA
Semiconductor Products Inc.
AN907A
Application
Note
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INTRODUCTION
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This application note provides information for progrmn-
'"''i}t:.~3Referto the attached schematic diagram. In the actual pro-
*.?,,
ming early mask set versions of MC1468705G2 MCU
*~~*'Si grarnming circuit, connect jumpers Kl, K2, K3, and K4 as
EPROMs (mask sets MJ3, 1MJ3, and 2MJ3) as we~ as subse- ,,JS '"
follows:
quent mask set versions. The schematic diagram at the e~~ of'
this application note defines a circuit with simple ju@?@g
which can be used when programming devices ~~$~~~ 'of
the mask set versions. In addition to the sche@l$
d~rarn,
the programming steps for each different ~~~~}~~?version
are included. The ( )MJ3 mask sets area~~~w
1%the next
section. Ml subsequent and future ,rnaW&* versions are
covered in the third section.
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PROGWWNG
THE ( )~%~P#K
SET VERSIONS
The MC1468705G2 CMQ~~&~&OM MCU with a date
code MJ3XXXX or lMJ~~-*@
incorporates the EPROM
programmable
mask,,,&tio~t#gister
(MOR). The following
options are availab~et~..t~, ~
1. Crystal oscwa&r&OR
bit 7 = O); bit 7 = 1 for XTAL
2. Divide-by~~Wlator
(MOR bit 6= O); bit 6=1 for: 2
3. Edge-~M@
interrupt trigger input (MOR bit 4= O);
bit:.k='~:i$or edge-sensitive and level-sensitive trigger
k*t.
y
,$ , >+.
;,>> '8.,.,,..
,,a,
'j,.<.>
'\?;kt..i:.'
...~>..
NOTE
@~r.,.,~ese options, while programmable,
are affected
t~~~y
the POWER-ON
substrate
currents and, at
" times, can latch in an incorrect value. This anomrdy
is usually corrected by an additiond RESET of the
MCU.
The MC1468705G2 CMOS EPROM MCUS with date code
2MJ3XXXX are identicd to the standard MC1468705G2,
except that the mask option register (MOR = $10) has been
permanently altered as follows:
1. Crystal oscillator (MOR bit 7= O)
2. Divide-by-4 oscillator (MOR bit 6= O)
3. Edge-sensitive and level-sensitive interrupt trigger input
(MOR bit 4= 1)
1. Connect
K1 jumper
between pins 1 and 2 if an
MCM2532
type EPROM
is used
as U2.
If an
MCM68764 EPROM or MCM68766 EPROM is used as
U2, connect K1 jumper between pins 5 and 6. These
connections ensure that the input to pin 21 is either + 5
V to Vpp if an MCM2532 is used, or a logical zero to
A12 if an MCM68764/66 is used.
2. Connect K2 and K3 jumpers between pins 1 and 2 to en-
sure correct LED input from PD5 and PD6.
3. Connect jumper K4 between pin 1 and pin 2 to ensure
that the address decoder (U3 and U4) output drives the
E (enable) input to U2.
Since
the
actual
EPROM
memory
used
in
the
MC1468705G2 is 2106 bytes, the EPROM device (U2) used
in programming only needs 4K bytes of memory location.
Figure
1 shows
the
memory
location
in which
the
MC1468705G2 program should be stored in an MCM2532,
an MCM68764, or an MCM68766 EPROM.
NOTE
Program $00 at memory locations $8BO through
$8F5 as wefl as in the MOR at location $FF5 in the
MCM2532, MCM68764, or MCM68766 EPROM
(whichever is used).
Prior to programming
the MC1468705G2 EPROM,
it
shotid be erased by exposure to high-intensity ultraviolet
(UW light with a wavelength of 2537 angstroms. The recom-
mended integrated dose (UV intensity x exposure time) is 40
Ws/cm2. The UV lamps should be used without shortwave
filters and the MC1468705G2 shodd be positioned about one
inch from the UV tubes.
OMOTOROLA
INC., 1985
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