Fig. 2.14 Locations Of Dip Switches; Fig. 2.15 Dip Switch Status Read Circuit - Epson MX-80 Technical Manual

(6) 74LS367
The 74LS367 is assigned to the external memory address space (DOOH-EFFH) of the
8049.
Since varied requirements may exist among the users of the MX-80 and modifications to
the functional specifications of the MX-80 may be called for by the users to satisfy such
requirements, two DIP switches are provided in this memory space on the control circuit
board. The DIP switches consisting of an 8-pin switch (SW1) and a 4-pin switch (SW2)
permit changes to the functions of the MX-80 according to the user's requirements, and
the status of each DIP switch can be read under the software control of the 8049.
Fig. 2.14 shows the locations of the DIP switches and Fig. 2.15, the DIP switch status
read circuit. (Refer to the Operation Manual of the MX-80 for the functions of the respec-
tive DIP switches.)
DIP SW2
DIP SW1
Fig. 2.14 Locations of DIP Switches
- --
--
_.
To RD of 8049
J '
113
11
, 7 9
12
J
4 , •
J
L~
,
2 J
\,~
L5367 (3A) L5367 (4A) G'
11 2 3 4 5
I)
G 15 11
I,
'1"
4
15'1' 15'1" 14
~~ ~J ~j
r"
~
+,
()K.7
'/' lSW1
'; 4
~ ~
~ ~8
@
•
I
' /
~:W2
•
i~~~2
2C
~
4
I
Fig. 2.15 DIP Switch Status Read Circuit
2-17
REV. A