Chapter 2 Installation of OEM7 Family Receiver Cards
OEM7 Installation and Operation User Manual v4
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of P1802 (USER1) LOW or HIGH respectively at boot time.
The OEM729 receiver samples pin 2 during the boot sequence to determine the mode for
COM1.
By default, RS-232 is selected since the pin 2 input, if open, is pulled LOW by an internal pull
down resistor.
To select RS-422, pull pin 2 of P1802 to 3.3 VDC during start-up.
Do not apply 3.3 VDC directly to pin 2. NovAtel recommends using a 1 kΩ resistor to pull
pin 2 high.
See
on page 158 for pin-out details for COM1 RS-232 and RS-422
configurations.
OEM729 Multiplexed Port
A third serial port, COM3, is also available on pin 7 (RXD) and pin 19 (TXD). By default, COM3 is
enabled. COM3 is multiplexed with both EVENT2 and USER0.
Figure 16: OEM729 COM3 Multiplexed with EVENT2 and USERGPIO
To enable COM3:
1. If a user application is running, make sure it does not initialize GPIO_USER0.
2. Issue the following command:
MARKCONTROL MARK2 DISABLE
3. Issue the following command:
INTERFACEMODE COM3 NOVATEL NOVATEL ON
Use any interface mode except
NONE
To enable MARK2:
1. Issue the following command:
MARKCONTROL MARK2 ENABLE
2. Issue the following command:
INTERFACEMODE COM3 NONE NONE OFF
Refer to the
OEM7 Commands and Logs Reference Manual
for further command information.
