Garmin GNC 420 Maintenance Manual page 157

NOT USED
ROT_R_LRGA
ROT_R_LRGB
ROT_R_LRGC
ROT_R_SMLA
ROT_R_SMLB
ROT_R_SMLC
GND
ROT_R_SW
UD1..UD8
PHOTOCELL
5V_MISC
NOT USED
NOT USED
NOT USED
LED_COMMON
B.3.6 J14
Pin # Pin Name
1 ROT_L_LRGC
2 ROT_L_LRGB
40 ROT_L_LRGA
3..22 CARD_A01..A20
23 CARD_RDN
24 CARD_WRN
25..32 CARD_DL0..7
33 POT_TOP_SW
34 PWR_ON_2
35 POT_TOP_PWR
400 SERIES MAINTENANCE MANUAL
P/N 190-00140-05
Table B-7. J12 Descriptions (continued)
25
64 I Rotor Right Large A to C are the contacts of a single pole
triple throw switch. The common of the switch is ground.
26 I
Only one of the 3 is low at a time.
27 I
61 I Rotor Right Small A to C are the contacts of a single pole
triple throw switch. The common of the switch is ground.
62 I
Only one of the 3 is low at a time.
63 I
28 O Ground.
29 I Push switch on right rotary. Active low input.
38..45 O UPPER half display DATA output.
51 I Photocell input is used to by the board to measure light
level. Photocells are resistive loads that change with
ambient light level.
56
57 O
58 O
59 O
60 O Led common is a 4 kHz PWM output that controls bezel key
and nomenclature backlighting. The longer this signal is
low the brighter the LEDs will be.
Table B-8. J14 Descriptions
I/O
I Rotor Left Large A to C are the contacts of a single pole triple
throw switch. The common of the switch is ground. Only one of
the 3 is low at a time.
O Card Address 01 to 20.
O Card Read Not. Output pulses low typically for 150 ns or 210 ns
depending on the number of wait states when cards are accessed.
O Card Write Not. Output pulses low typically for 180 ns when
cards are accessed.
B1 Card Data Left Bit 0 .. 7. These pins float except during card
accesses.
I Push switch on top pot. Active low input.
I Power on number 2 contact. Powers unit on when connected to
PWR_ON_1.
O Provides Power to top pot.
Description
Page B-7
Rev. C