- How is it like with operating temperature of TRs?
All components and technologies used for TRs meet Industrial or Automotive temperature ranges. TRs work in lower temperatures like other electronic devices with the following limitations:
- RF range decreases with lower temperature.
- Dry frost does no harm but no ice accretion is allowed. This has a strong impact on RF.
- Humidity > 85 % and condensed water should be avoided.
- All TR series TR-5xDx and higher have Industrial temperature range -40 °C to +85 °C declared.
- Is low supply voltage detected?
Yes, but not automatically. It is possible to perform the check as follows:
For DPA approach:
- The Coordinator can monitor supplying of all Nodes using the OS peripheral and the Read command.
- When using the DPA value, information about power supply is included in every response.
- IQRF OS function getSupplyVoltage is available. See IQRF OS Reference guide. In case of TRs with an LDO voltage regulator (e.g. TR-72D), the resulting value corresponds to the LDO output but not to the battery voltage.
- What are the requirements for TR sealing?
See the answer in chapter HW design.
- How much time does TR transceiver need to be ready after power on?
About 250 ms.
During the initialization, the following tasks are performed: waiting for establishing proper power supply, additional time delay for reliability, OS initialization, user RAM clearing, calibration of system RC clock and detection of possible request to enter programming mode.
- Is there any limitation when using TR I/O pins during an IQRF IDE debug session?
IQRF IDE uses an SPI interface to control a debugging session of the TR module. Therefore a usage of certain Cx pins of the TR is slightly limited during debugging. C5, C6, C7 must be configured as input pins and C8 must be configured as an output pin. This pin configuration is set by default by IQRF OS after reset. If this is changed by an application program, it must be restored back before calling the debug() function.
- Why do LP and XLP modes depend on the noise?
In LP and XLP modes, the TR is sleeping almost all the time and wakes up periodically just for short moments, checks incoming RF signal and falls asleep again if no one is detected (either it is a correct IQRF packet or an interference/noise).
Thus, due to the noise, the TR unnecessarily stays receiving which increases the power consumption. Therefore, to avoid attempts to receive such undesired signal (which is usually weaker than a correct IQRF packet), filtering of RF signal is necessary in these modes. It is automatically performed by IQRF OS on the certain level. In a noisy environment this level should be increased by the checkRF(level) function.
However, stronger filter causes shorter RF range. See the TR datasheet, Diagram Relative RF range vs. level in the checkRF(level) function.
- How to implement a user-specific timing?
Besides of IQRF OS timing functions like waitMS and startDelay, the Timer6 HW timing module inside the MCU is available for the user. For application under IQRF OS, see the MCU datasheet and example Servo, one of the Advanced examples from IQRF Startup package. Under DPA, see example CustomDpaHandler-Timer.c.
- How to implement A/D converter?
- How to implement UART?
- How to implement Dallas 1-wire bus?
- How to implement SPI Master?
- How to implement PWM?
- What is the payload data throughput?
The bit rate 19.8 kb/s is a theoretical value of a raw data stream. The feasible payload data throughput is significantly lower. The packets must be equipped with auxiliary data, there are various necessary system overheads, limitations due to local regulation etc. In IQMESH, it also depends on the time slot length and number of hops.
- What is the packet propagation time?
See the IQRF US User's guide, chapter RF transmitting, table RF packet propagation time.
- What is the precision of temperature sensor?
The accuracy is ±0.5 °C (from -20 °C to 85 °C) and ±1°C (from -40 °C to -20 °C). The resolution is 0.5 °C. The measurement takes about 3 ms. See Example E08–TEMPERATURE .
- Is it possible to communicate between IQRF TR and a 3rd party transceiver?
- Do TRs meet the regulations required for wireless fire alarms?
See the answer in chapter Regulations and certification.