Crate pamoja_radios 

LoRa radio drivers for the pamoja SDK.

pamoja-lora works out what a link costs and how far it reaches; this crate puts a radio on the air to match. Each chip family has a module in two halves. The first is the chip’s commands or registers and its decoders: the bytes that configure it, the interrupt and status bits it answers with, the signal levels of a received packet, and the frequency, modulation, packet, and power settings that a LinkSettings and a channel plan turn into. That half needs no bus and no allocation, so a test, a language binding, or a protocol analyzer can use it without a radio. The second half is an embedded-hal driver that talks to the chip over SPI and transmits and receives frames.

• sx126x - Semtech’s SX1261, SX1262, and LLCC68, from the SX1261/2 datasheet.
• sx127x - Semtech’s SX1276, SX1277, SX1278, and SX1279, and modules such as the RFM95W, from the SX1276/77/78/79 datasheet.
• radio - one radio of either family behind the same calls: configure from a carrier, a link, and an output power, then transmit, receive, and listen.
• duty - a guard that holds a radio silent for the off time a regional duty-cycle limit requires after each transmission.
• lorawan, with the lorawan feature - a LoRaWAN Class A node: an end device from pamoja-lorawan driving a radio, with its receive windows opened on time.
• relay, with the lorawan feature - a LoRaWAN relay driving a radio: it scans for wake-on-radio frames, answers them, and forwards the uplinks behind them.
• linux, with the linux feature - opening a radio on a Linux board over spidev and the GPIO character device, with a plain error on every other platform.
• mesh, with the std feature - a pamoja transport over a radio, carrying topics in pamoja-mesh frames that each node relays onward, under the duty-cycle guard.
• sim, with the sim feature - simulated SX126x and SX127x chips that answer the drivers with no radio attached, and report what they were tuned to and what they sent.

Examples

A node on EU868 works out how it may transmit before it touches a radio: the link its data rate names, how hard its amplifier may drive through its antenna under the plan’s ceiling, and how long it must stay silent after each reading.

use pamoja_lora::budget::{Decibels, LinkBudget};
use pamoja_lora::region::Region;
use pamoja_radios::duty::DutyCycle;
use pamoja_radios::radio::{RadioConfig, SyncWord};
use pamoja_radios::sx126x::config::{PowerAmplifier, TxPower};

let eu868 = Region::Eu868.plan();
let carrier = 868_100_000;
let link = eu868.link_settings(3).expect("DR3 is a LoRa data rate");

// A 2.15 dBi whip on half a decibel of pigtail: the amplifier drives only as hard as
// keeps the radiated power under the plan's ceiling at that carrier.
let whip = LinkBudget {
    transmit_antenna_gain_dbi: Decibels::from_hundredths(215),
    transmit_cable_loss_db: Decibels::from_tenths(5),
    ..LinkBudget::default()
};
let ceiling = Decibels::from_db(eu868.max_eirp_dbm(carrier).into());
let power = TxPower::under_ceiling(PowerAmplifier::HighPower, &whip, ceiling);
assert_eq!(power.setting_dbm, 14);

// The configuration an SX126x or an SX127x takes, as a LoRaWAN device uses it.
let config = RadioConfig::new(carrier, link, power.setting_dbm).lorawan_device();
assert_eq!(config.link.spreading_factor(), 9);
assert_eq!(config.sync_word, SyncWord::Public);

// Under the band's one percent duty cycle, a ten-byte reading owes ninety-nine times
// its airtime in silence before the next one may start.
let mut guard = DutyCycle::new(10);
let airtime = guard.transmitted(0, &link, 10);
assert_eq!(guard.wait_us(airtime), 99 * airtime);

Modules

duty

A duty-cycle guard for a radio.

linux

Opening a LoRa radio on a Linux board.

mesh

A pamoja transport over a LoRa radio, carrying topics in pamoja-mesh frames.

radio

One LoRa radio of either family, behind one set of calls.

sim

Simulated SX126x and SX127x chips, for running a radio program with no radio attached.

sx126x

Semtech SX1261, SX1262, and LLCC68 transceivers.

sx127x

Semtech SX1276, SX1277, SX1278, and SX1279 transceivers, and the modules built on them such as the RFM95W.

sx1302

Semtech SX1302 and SX1303 concentrators.