Motorola GM950E Service Manual page 222

Accessory Connector Details
Pin 6.
- BUS+
This connects to the radioÕs SCI serial bus which is used for programming and tuning the radio. The
line is also available at the microphone connector Pin 7.
Pin 7.
- Ground
Used as ground for both analogue and digital signals.
Pin 8.
- General purpose 3 (GP3)
This is a digital input/output and is also available on the internal option connector (J0103:7). The
RSS details which functions may be assigned to this pin by the codeplug. (See Notes 1 and 2).
Pin 9.
- General purpose 4 (GP4)
This is a digital input only. It is also available on the internal option connector (J0102:7) and is used
in input capture mode when a serial type option board is Þtted. The RSS details which functions may
be assigned to this pin by the codeplug. (See Note 1).
Pin 10.
- Ignition sense
Connecting this line to the ignition line of the vehicle will automatically turn the radio on when the
ignition of the vehicle is turned on. When ignition is connected, the radio cannot be turned off as long
as the ignition is active. When this line is at 0V or not connected, power on/off is under manual
control. Resistor R0423, 4.7kW, which is not Þtted as standard will cause the radio to be permanently
on whenever 12V is connected to the main power connector.
Pin 11.
- RX Audio Discriminator/Filtered (Analogue output)
The signal routed to this pin is controlled by AFIC. There are two possible outputs; continuous
discriminator audio or continuous Þltered RX audio output of AFIC. The output mode can be selected
by the RSS, however, this mode may be overridden during certain tuning operations. For
discriminator audio, the nominal ouput level is 330mVRMS for 60% deviation. The impedance is
600ohms. For Þltered audio, the nominal ouput level is 600mV for 60% deviation. The impedance is
600ohms.
Pin 12.
- General purpose 5 (GP5)
This is a digital input/output and is also available on the internal option connector (J0103:8). The
RSS details which functions may be assigned to this pin by the codeplug. (See Notes 1 and 2).
Pin 13.
- Switched B+ / Analogue Ground
The output of this pin may be conÞgured by a solder link within the radio. Switched B+ is the default.
The current limiting resistor (R0455) default is 0W, therefore extreme care must be taken to avoid
short circuiting this output to ground, which will damage the radio.
CAUTION: The maximum continuous current allowed is 300mA. A suitable external fuse must be
Pin 14.
- General purpose 6 (GP6)
This is a digital input/output and is also available on the internal option connector (J0102:3). The
RSS details which functions may be assigned to this pin by the codeplug. (See Notes 1 and 2).
Pin 15.
- RSSI
Received Signal Strength Indication, buffered analogue voltage.
Pin 16.
- Speaker+ audio
Positive output of radioÕs audio PA (see Pin 1).
B-2
installed into the lead to pin 13 to avoid damage to the radio.
Note 1: Digital Input
4.7 kW Internal Pull Up Resistor to +5V.
Maximum Input Voltage accepted as Low = 0.6V
Minimum Input Voltage accepted as High = 3.0V
Note 2: Digital Output
4.7kW Internal Pull Up Resistor to +5V
Maximum Current when Output Low = 10mA
Maximum Voltage when Output Low = 0.5V @ 10mA
Note 3: High Current Digital Output
4.7kW Internal Pull Up Resistor to B+
Maximum Current when Output Low = 200mA
Maximum Voltage when Output Low = 1.7V @200mA
External Device Connectors