Figure 3-31. Gcai Signal Configuration; Side Controls - Motorola APX 3000 Detailed Service Manual

Theory of Operation
: Controller

3.2.6.2 Side Controls

The side controls include four programmable, buttons (Side Top Button,Side Middle Button, Up
arrow and Down arrow). These components interface to the main flex via a connector through side
control flex. The main flex routes the side controls signals to main board through connector J1. See
Chapter 7 for pin out names and numbers.
Up Arrow Button (R4006), Down Arrow Button (R4007) and the top side button (R6101) are inputs to
the CPLD and are biased to 1.875V. A button press is detected when the OMAP reads a 'LO' state
from the CPLD EMIFS interface. Middle side button (R4005) is connected directly to OMAP and a
button press is detected when a LO state is read.
3.2.6.3 GCAI
The GCAI (Global Communications Accessory Interface) connector is a 15 pin interface located on
the side of the radio. The connector interfaces the radio with accessories and is used for
programming. When the OMAP (U6501) detects that an accessory has been attached through a
logic low on GPIO0, it will identify the device by reading the GCAI_ONE_WIRE line. Once the device
type is identified, the appropriate signals are multiplexed through MAKO to the main flex connector
for the particular device.
Mounted to the side connector is a flex that houses ESD protection circuitry. The universal side
connector interfaces with the main flex via the J2 connector of the main board. The figures below
show the connections and signal assignments from the universal connector to the controller board.
OMAP1710
One-Wire
USB
PORT 0
UART1_RX
UART1_TX
GPIO
GPIO
GPIO
CPLD
GPO
Figure 3-31 is a block diagram of the GCAI interface.
ONE_WIRE
TXEN
DAT
SE0
UART1_RX
UART1_TX
OPT_GPIO_3
OPT_GPIO_2
OPT_GPIO_0
MACE

Figure 3-31. GCAI Signal Configuration

MA KO
ONE_WIRE_GCAI
BATT_STATUS
VBUS
D+
USB
D-
XCVR
SPKR+
EXT
SPKR-
PA
MIC+
Ext Mic
MIC-
Preamp
KF Switch
OPTA_SEL_2
OPTA_SEL_1
OPTA_SEL_0
KEYFAIL
KEYFAIL CONTROL
GCAI
CONNECTOR
GPIO_0
One-Wire
1
2
Vbus
3
D+
4
D-
5
GND 6
7
8
GPIO_3
9
10
11
12
GPIO_4
3-39