This module will communicate with other modules, including the flight computer through the main I2C bus. The purpose of this module is to interface with the Iridium 9602 Satellite Data Modem, and optionally two external serially .
Google Spreadsheet Comm Ctrlr BOM
Main Onboard Devices:
See designguide
See Arduino FIO documentation
Pin | Function |
1 | PWR12 |
2 | GND |
3 | PWR12 |
4 | GND |
5 | Power Enable |
6 | GND |
7 | SAT Host Serial Port RX |
8 | SAT TX |
9 | SA Satellite Available |
10 | DA Data Available |
11 | Debug Serial Port TX |
12 | Debug Serial Port RX |
13 | SAT Host Serial Port RTS |
14 | SAT Host Serial Port CTS |
Pin | Function |
1 | PWR12 |
2 | PWR3.3 |
3 | PWR5 |
4 | GND |
5 | Serial data from ExtTX |
6 | Serial data to ExtTX |
Pin | Function |
1 | PWR12 |
2 | PWR3.3 |
3 | PWR5 |
4 | GND |
5 | Serial data from ExtTX |
6 | Serial data to ExtTX |
Pin | Function |
1 | PWR12 |
2 | GND |
3 | External I/O 1 |
Command | Action | Data Required | Format | Sat Uplink ok |
---|---|---|---|---|
0x00 | Transmit ATC Short Report | 12 bytes | See Note below | |
0x01 | Transmit Data from I2C EEPROM | 4 bytes | 2B Start Addr, 2B End Addr | |
0x02 | Update HF Telemetry values | 3 byte | Val0, Val1, Val2 | |
0x03 | Transmit HF short position report | 0 byte | ||
0x04 | Set HF transmit rate | 1 byte | ASCII 'H', 'M' or 'L' | |
0x05 | Mute HF for 2 minutes | 0 byte | ||
0x06 | Reset cutdown heartbeat timer | 0 byte | Y | |
0x07 | Set cutdown timer to X minutes, and reset | 1 byte | 0-255 | Y |
0x99 | CUTDOWN NOW | 0 bytes | Y | |
0xBB | Power up sat modem | 0 bytes | ||
0xAA | Power down sat modem | 0 bytes |
For radio interfacing details see also:
The The m10 will toggle a logic line high when it has received a message. This signal should interrupt wake up the communications module MCU if it is in sleep mode. The MCU should then read in the message from the m10 module, and pass it on to the appropriate destination. The address of the destination module will be part of the 5-byte command.
The balloon cutdown module will have a short cutdown timer. This timer will be on the order of 30 minutes or so. The timer will be reset by an I2C message from the comms module every time the comms module receives any message from the satellite modem. That means, in addition to forwarding the uplinked message over the I2C bus, you will need to immediately send a direct “reset the counter” heartbeat I2C message over the bus to the cutdown module.
Message content destined for the sat modem or HF modem will be passed raw from module to module if possible, this will reduce the need to change firmware on the comms module.
Messages to be transmitted are to be transmitted immediately upon receipt by the comms module.
Comms module should be able to respond with a configuration request listing which radios are connected (Sat, HF, VHF). Also should have a status available of all radios, with information such as:
Bold indicates REQUIRED connections for flight.