Sharp ER-A750 Service Manual page 13

PWB marking
(ER-03MB/04MB PWB Face side)
Imprint " " on this white area.
Packing case
Imprint " " on the right side of the
model rabel.
Colleclive case
C
E
Imprint " " under the model label.
Indivi dual case
C E
2) Cautions to be exercised when using the RAM
PWBs with the ER-A750
When using the above-mentioned RAM PWB version (1) with the
ER-A750, it is necessary to correct the RAM access timing. Use of
the above-mentioned RAM PWB version (2) does not require the
correction of the RAM access timing. For this purpose, a hardware
jumper (JP1), designed to judge to determine whether or not to
correct the RAM access timing, is located on the main PWB of the
ER-A750 (Fig. 2). Before installing an optional RAM PWB, check its
version by referring to the description given in the above-mentioned
(1) and (2) and set the jumper as shown below. (The ER-A750 has
been factory-set for 150ns access time and TP cycle inserted.)
IN case of (1)
IN case of (2)
Fig. 3 Setting of the JP1 on the main PWB of the ER-A750
(1) Setting when the ER-03MB or the ER-04MB is not marked with
"| "
(Position to which the ER-A750 has been factory-set)
(2) Setting when the ER-03MB or the ER-04MB is marked with "| "
3 – 3
MAIN PWB
JP1
B C E
Q6
Short position
1 3
1 3