3.6 Software

3. MSC Interfacing

The radio supports 3 modes of digital communication and the RF link. The digital modes USART, SPI and TWI share the same input and output buffer and cannot be operated simultaneously. Commands can be accepted via all digital communication modes any time the buffer is not being processed, using only one communications mode at a time. All packet formats can be disabled from direct access preventing accidental commands requiring HDLC packet encapsulation.

3.6.1 MSC SW Packet Communications (below)

3.6.1 MSC SW Packet Communications

Packet commands are used to change/query a setting or to send packet data.

      • The settings are reconfigurable and non-volatile, configured to meet the mission needs.

      • Transmit packets are internally buffered and transmitted when the port is open and there are no receive packets being processed.

All interactions are packet based. Only acceptable packets are processed. Each packet has a specified start and stop byte.

Packet Types:

      • HDLC encapsulation

HDLC packets are used to encapsulate other packets to provide reliable communications. The frame includes start and stop flags, an address field, a control field, an information field and a frame check sequence.

      • Settings

          • General settings

              • USART

              • TWI

              • Temperature & Voltage

              • AX.25 Defaults

              • HDLC Packet Default

              • Packet Format Disable

              • Housekeeping Settings

          • TX settings (for each of 4 ports)

          • RX settings

      • Transmit packet

      • Receive packet

      • Output pin command

      • Special Functions