User's Manual

Model 1150A DVOR
2-30 Rev. - November, 2008
This document contains proprietary information and such information may not be disclosed
to others for any purposes without written permission from SELEX Sistemi Integrati Inc.
The RF Monitor contains a temperature sensor U11 attached close to the heat sink to monitor the temperature of the
heat sink. The RMS has the ability to read the temperature through the SPI interface. The signal SPI_SCK is the
clock used to clock in and out the serial data. The SCK signal is buffered by U8A. The SPI_MOSI (master out slave
in) line is serial data coming from the RMS. Data on this line enters U8A pin 2 and is buffered and exits at the
Y1output. The signal ~SPI_CS2X is active low when the RF Monitor board is being addressed by the RMS. Clock
and data information is always present but ignored by the RF Monitor when the ~SPI_CS2X is high.
Buffer U8 is used to buffer the SPI_MISO data out of the RF Monitor to the RMS. The output at Y1 is tri-stated
when the data is a high and active low when the data at the ~OE goes low. This allows for many of the other
modules to use the same SPI_MISO line back to the RMS. Resistor R58, R59,R60, R61 and U13 are used to decode
the addressing of the RMS so that the RF Monitor responds to the correct ~SPI_CS2X and address. The circuit U13
provides for parallel input output from the RMS SPI port. This allows for selection of either the temperature sensor
U11 or EEPROM U10. The EEPROM is used to read and write data from the RMS. This EEPROM holds the Rf
Monitor serial number and revision information programmed by the technician through the PMDT screens.
2.3.2.9
RMS Processor Block Diagram Theory
Refer to Figure 2-12. The Remote Monitoring System (RMS) CCA performs communications via thirteen serial
ports plus a parallel port, and facilitates monitoring/control in a single or dual VOR system. The RMS CCA receives
battery-backed DC power from the BCPS CCAs at connector J2, through OR’d diodes, and regulated to +5V and
+3.3V supplies for use by the RMS CCA to power the microcontroller and all of its associated circuitry.
The U8 microcontroller utilizes external flash ROM, non-volatile RAM (NVRAM), synchronous dynamic RAM
(SDRAM), a voltage supervisor/watchdog reset circuit, and an oscillator to form the core microcomputer. The U8
microcontroller also includes a direct memory access (DMA) controller, serial ports, and general purpose
input/output (I/O). Microcomputer peripherals include a real-time clock (RTC), universal asynchronous
receiver/transmitters (UARTs), a parallel port interface (PPI), a USB host port, a USB slave port, off-board bus
buffers, and more general purpose I/O.
The U8 microcontroller’s flash ROM is factory programmed using the J4 SPI boot header while factory debug is
accomplished using the J3 emulator header, the JP3 debug header, and the JP4 PMDT RS232 header. None of the
aforementioned connectors and headers will be used by the customer in the field.
RMS communication to the LCU CCA occurs via the parallel port established by U29 through U32 and connector
P1. The LCU also returns system control signals through P1 such as *TEST (lamp test) and *MRESET (master
reset). Configuration switches on the Backplane CCA define the system set-up to the RMS when it reads them via
the Facilities CCA through the external address/data bus on connector P2.
The U8 microcontroller communicates serially through one internal and twelve external UARTs. The internal
UART is the debug port of JP3. The other twelve UARTs control communications to Monitors 1 and 2, Audio
Generators 1 and 2, Remote Maintenance Monitor (RMM), Spare #1, Radio Modem, LCD, BCPS, Spare #2,
Ethernet, and the PMDT. Two options are possible for local PMDT communications. The PMDT may be connected
to USB connector J1 with header JP2 strapped for USB operation. The second option (in factory only) has the
PMDT connected to RS232 header JP4 and header JP2 strapped for RS232 operation.
These eleven external UARTs (not including the PMDT) route to connectors P1 and P2. The host USB port of
connector J2 is available for possible future options such as connection to a printer.