SubGig Radio Module
What serial port settings should I use in Tera Term to talk to the SubGig module?
The SubGig module defaults to 9600 baud for compatibility with older systems and simple Arduino based gateways. Use the following settings: 9600 baud 8 bits data no parity 1 stop bit no flow control Type “AT” without the quotes to see an “CMD_OK” ...
Is there a test mode I can place the module in to verify that I have a radio output?
Yes, use the Test Carrier (TC) AT command. To turn the test output on send the module “ATTC1” and to turn it off send it “ATTC0”. The test carrier will stay on until it is turned off or power cycled. Do not use this mode on battery powered devices as ...
The user guide says that the BridgeBee modules are designed for IoT applications. Can I connect the module to the internet?
Short answer, no not directly. The moduleis designed for IoT systems requiring wireless monitoring and control. The module itself is an easy to use wireless connectivity product that links gateways to sensors or other endpoint devices that require a ...
The user guide mentions a published SubGig spec. Where do I find that?
The SubGig specification has not yet been published, however a brief description of the topology is given in the user guide.
The user guide mentions has a table that gives the Baud, Stop Bits and Parity for the UART connection, but not the number of data bits – is it 8 data bits?
Yes 8 data bits
What is the difference between a coordinator and an endpoint?
The SubGig standard defines a very simple star topology where one coordinator device speaks to multiple endpoints. The coordinator is generally controlled by a host processor, typically on a gateway connected to the cloud. A device acting as a ...
Where do I download the Radio Bridge configuration app?
The configuration app is still in development and not yet released. However, all functions can be accessed through a simple terminal emulator such as Tera Term. The configuration utility is a fancy terminal emulator that allows you to enter values ...
What is the AT command to enter the bootloader?
The AT command is: BL. Note that the bootloader runs at 115200 baud so it is best to first change your baud rate to 115200 (ATBR7), do a write to flash (ATWR), and then enter bootloader (ATBL). After you update the firmware, the default baud rate of ...
Is there a way to query the module for a list of enrolled devices?
Yes, this command is for coordinator devices only: LI (list endpoints). Each endpoint ID will show up in a list separated by newline characters and terminated with a “CMD OK” line.
What happens if you try to add a device using the DE command and a device trips that is already learned? Does it take up another slot in memory?
No it will not take another slot. When an endpont is added, whether through the DE (discover endpoint) command or manually using the AE (add endpoint) command, if the endpoint already exists it will not be duplicated.
Is it possible to queue up multiple message to go to the same device?
No, you can only queue one message at a time for a particular endpoint. Each endpoint has its own queue that is independent of the others. The purpose of the queued message is to immediately send a message to a sleepy endpoint when it has waken up ...
Is there a way to make the coordinator set the Supervisor Timeout in the endpoints when the coordinator has its Supervisor Timeout changed?
Currently there is no way for the coordinator to change the supervisor period of the endpoints dynamically. The supervisor is a basic system health check where the endpoints report their current status to the coordinator on a periodic basis (often on ...
Is there a default PK that comes in all modules from the factory or how do I find out what it is?
The provisioning key is not set by Radio Bridge, it is a write-only field that is set by the client prior to deployment into the field. The session key itself could be programmed into every device and the provisioning key would not be necessary. The ...
Instead of sending the SK in 2 AT commands (KU and then KL), is there some AT command that allows it to be sent as one command?
There is no command which sends both parts automatically, they must be sent individually. Also, it doesn’t matter which order they are sent, as long as both parts of the key are received by the endpoint, encryption will be enabled automatically.
If I’m changing the Session Key, does it matter if I set the upper (KU) or lower (KL) first?
No it doesn’t matter, you can transmit in either order. When the endpoint receives both the upper and lower half of the key it will enable encryption automatically. Also note that the KU and KL commands are only used to transmit the session key from ...
What order is the data sent in the KU/KL AT commands?
The KU/KL commands assume that the session key is already set at the coordinator. So to transmit keys from the coordinator to an endpoint the following steps must be used: Set the Provisioning Key using the PK command on both the coordinator and ...
In order to save power, can the coordinator send a PL command over the air to each endpoint?
No this is not a way to remotely change the power level. Also, we do not allow coordinators to dynamically change the listen window for endpoints. The reason for this is that a sleepy endpoint is typically battery powered and dynamically extending ...
Since the PL command accepts a 32-bit value, is the permissible value for that command 0x00000000 to 0xFFFFFFFF?
Yes but note that the power level parameter is a signed value because it represents units in dBm (actually deci-dBm or dBm/10). So for instance, to set a power level of -10 dBm one would write FFFFFF9C (-100 in hex). If this parameter is used, the ...
What is the Governor?
See the RBM101S User Manual under the section “Governor” for more detail. In short, the governor prevents the user from violating FCC requirements at the 315MHz band which is subject to FCC part 15.231. If the user violates the bandwidth and/or ...
How do I use the test packets generated by the TP command? Do I get some sort of status report back that tells me the number of packets that were/weren’t ACKed?
The Test Packets command just puts the device into a test mode that sends a random stream of packets until it is told to stop (ATTP0). The Test Packets command is typically used to measure RF characteristics and the packets are not designed to be ...
How does the duplicate filter work?
If you have 2 devices, A and B, and each are sending duplicate packets but are received interleaved, the question is whether all 4 packets come through or just 2. For example consider the sequence: A B A B Short answer is 2, but that is dependent on ...
Can the coordinator remotely change the Listen Window in endpoints?
No we do not allow coordinators to dynamically change the listen window for endpoints. The reason for this is that a sleepy endpoint is typically battery powered and dynamically extending the listen window in the field could unexpectedly and ...
Can the coordinator queue one message for each endpoint, or does it only queue one message in total?
There is a single slot in the queue for each registered endpoint. Thus, multiple endpoints may have queued messages simultaneously, but only one message can be queued for each endpoint at any given time.
How would I get an error 001B? Would the module have to be getting flooded with RF messages? How do I make sure this doesn’t happen?
This is an internal error condition and there should be no way for a user to cause this. The module is built to be compliant with FCC bandwidth limitations and through the SubGig protocol there should never be a way to cause this.
How would a radio transmit underflow (error 001C) happen? I’m not getting this error, but I was just wondering what it would mean that I’m doing wrong if I were to see it.
That would simply indicate an internal error, there is no known way to create this error as a user.
Does the coordinator know which endpoints are sleepy ones, and can it give me a list of which ones are/aren’t?
In the next firmware release v1.02 we will have the command ES which will report endpoint status including the sleep mode of the endpoint.
If you have a message queued for a sleepy endpoint that has not gone out yet, and you want to change that message, can you?
The next firmware release v1.02 will have a CQ (Clear Queue) AT command for this purpose.
The manual mentions that in sniffer mode, the device ID is reported “of the associated endpoint” (6.4.2.3). Does that mean it cannot sniff message from other coordinators?
Yes, it will sniff out any packets whether it comes from a coordinator or endpoint. The sniffer is a special diagnostic mode and thus is not operating as either a coordinator or endpoint itself.
Is it possible to do an update to the modules over a wireless connection?
Short answer, no. The SubGig BridgeBee modules are designed to operate at 315MHz which is outside of normal ISM bands and is subject to FCC part 15.231. These requirements impose restrictions on bandwidth and thus to not allow for over the air ...
Is there a way to write code for the ARM processor on the Bridgebee module so that I don’t need an external micro to talk to the module?
No, the BridgeBee is a stand-alone radio module and interfaces to a host through the serial port. Thus, a user may not add application code on the BridgeBee itself. If a stand-alone module is required (such as what we have done with our sensor ...
When I try to read the BroadcastID Only setting (ATBO) or set it (ATBO0 or ATBO1) I get a reply that the command isn’t recognized (ERR 000A).
The ATBO command will be removed on the next firmware release. During the Discover Endpoint sequence on the coordinator, any packet from the radio will be used to add the associated endpoint to the list of connected devices. In other words, if the ...
Is there any AT command I can send the module to cause it to reboot?
There isn’t a reboot command that is the equivalent of pulling reset low, but you can use the RE (restore parameters) or FR (factory reset) to reset all parameter values to default. Note that the difference between the two is that FR also clears the ...
As I’m learning to use the module, I’m sending a lot of data. Is there a way to temporarily disable the governor without just using the Emergency Packet (EP)?
There is a hidden feature in the firmware to disable the governor, but since this invalidates FCC we do not publish it. If this is necessary, please email support@radiobridge.com to confirm that you understand that this will invalidate FCC compliance ...
If I put a packet in the queue, but then send out enough regular packets (SP) that the governor kicks in, what happens to my queued packet?
Queued packets are not saved if the governor is engaged. When the governor has hit the limit, any new send requests through SP or QP will be rejected with an error indicating that the governor is on.
Does the coordinator need to have its sleep mode enabled to send queued packets to sleepy endpoints?
No and you typically don’t want to put the coordinator into sleep mode. When the queue packet command is used the coordinator will check to see if the endpoint is sleepy, and if it is not then it will send the message immediately. In other words, the ...
Set a device in sniffer mode and write the configuration to flash, after reset would the device be in sniffer mode?
Currently the sniffer mode does not persist with writing the configuration to flash, but this will be added to the next firmware release.
If I only used AT sleep mode command without SLEEP_RQ, coordinator still receives STA 0001, is this behavior right?
The sleep mode command ATSM will enable or disable sleep mode, but does not put the device to sleep. If an endpoint has sleep mode enabled but it is not sleeping then the coordinator should not receive the STA 0001 (sleepy endpoint) status message.
What is the relation between SLEEP_RQ pin and sleep mode AT code, do I need both to enter sleep mode?
Yes, you need to first enable sleep mode on the endpoint using the command: ATSM1 and then pull the SLEEP_RQ pin high to enter sleep. Pull the pin low to exit sleep mode.
Can I wake the sleepy endpoint using AT command?
No, the serial ports do not run in sleep mode. To bring the endpoint out of sleep mode you need to set the SLEEP_RQ pin low.
Can I observe the output of ATTP on sniffer?
No you cannot see this on the sniffer. The ATTP command puts the device into a continuous stream mode that is used for verifying RF characteristics on a spectrum analyzer or other RF equipment.
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