Meter Bridge Module - Lexicon 960L Service Manual

9004 0004
9004 0008
9004 000C
9004 0010
9004 0014
9004 0018
9004 001C
9005 0000
9005 0004
9005 0008
9005 000C
9005 0010
9005 0020

Meter Bridge Module

The meter bridge circuitry is represented on schematic 060-13389. The module connects to the main board
via J4 (main board sheet 7). The meter bridge consists of 24 LEDs in a three row by eight column matrix.
The LEDs are divided into two groups, each controlled by an 8 bit register (U1, U2, sheet 1). Software
writes a sequence of bit patterns to activate the groups one at a time turning on the LEDs in that group.
RED
RED
TOP
GREEN GREEN
MID
GREEN GREEN
BOT
Group B1 Group B2
GPDR
GPSR
GPCR
GRER
GFER
GEDR
GAFR
ICIP
ICMR
ICLR
ICCR
ICFP
ICPR
RED RED
GREEN GREEN
GREEN GREEN
Group B3 Group B4
Figure 7-1 Meter Bridge
GPIO pin direction register
GPIO pin output set register
GPIO pin output clear register
GPIO rising-edge register
GPIO falling-edge register
GPIO edge detect status register
GPIO alternate function register
Interrupt controller IRQ pending
Interrupt controller mask register
Interrupt controller level register
Interrupt controller control register
Interrupt controller FIQ pending
Interrupt controller pending register
RED RED
GREEN GREEN
GREEN GREEN
Group A1 Group A2
Lexicon
RED RED
GREEN GREEN
GREEN GREEN
Group A3 Group A4
7-53