YORK INTERNATIONAL
117
FORM 150.62-NM7 (103)
.
TABLE 38 – KEYPAD PIN ASSIGNMENT MATRIX
KEYPAD PIN CONNECTIONS
STATUS 1 TO 5
OPER DATA 1 TO 7
PRINT 1 TO 6
HISTORY 1 TO 8
UP ARROW 2 TO 5
DOWN ARROW 2 TO 7
ENTER/ADV 2 TO 6
COOLING SETPOINTS 2 TO 8
SCHEDULE/ADVANCE DAY 3 TO 5
PROGRAM 3 TO 7
OPTIONS 3 TO 6
CLOCK 3 TO 8
3
KEYPAD
The operator keypad is connected to the microboard
by a ribbon cable, which is con nect ed to J2 on the mi-
cro board.
The integrity of a specifi c “button” on the keypad can be
ver i fi ed by doing a continuity check across two spe cifi c
points (or pins), that represent one of twelve “but tons”
on the keypad.
Table 38 lists the key/pin assignments for the key pad.
Power to the microboard must be turned off, and
the ribbon cable dis con nect ed from the mi cro board
prior to con duct ing the tests, or com po nent dam age
may result.
After the ribbon cable is disconnected from mi cro board,
ohmmeter leads are con nect ed to the pins rep re sent ing
the spe cifi c “button” to be tested. After connecting the
meter leads, the “button” being checked is pressed
and a reading of zero ohms should be ob served. After
re leas ing the “button,” the re sis tance value should be
in fi nite (open cir cuit).
Pin 1 is usually identifi ed by a stripe
on the rib bon cable.
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