After transmission we should change the state before invoking opening of
slots as we may start receiving in the rx slots and the state would
suddenly change from SENDING to RECEIVING without going through the
ACK_WAIT state (in case of CONFIRMED messages). Tests show that after
this slight adjustment, our number of ack retries have significantly
reduced.
LinkADRReq mac command can be used by the network server to set a
certain level of QOS using NbTrans field which is applicable to
Unconfirmed traffic only for 1.0.2 spec.
This commit introduces mechanisms to facilitate this QOS. It means to
repeat an outgoing unconfirmed message NbTrans times without changing
its frame counter.
For class C, we have retired the ack_expiry_timer_for_class_c and have
replaced it with another timer which mimics the RX2 closure as in Class
A but doesn't actually close RX2 window. It's just a mechanism by which
the state machine is informed that the you can proceed forward, we have
not received anything in RX2 window either. This is needed as RX2
doesn't timeout in class C (i.e., the radio remains in continuous mode).
In addition to that we need to close any pending timers for Receive
windows after the MIC has passed and the Duplicate counter check has
also been passed.
Before going after an automatic uplink, we should check if there was an
automatic uplink already ongoing, i.e., the ack for the previous
automatic uplink cycle has not been received.
If there is we shouldn't queue the new automatic uplink and wait for
the previous Ack cycle to complete.
While performing compliance tests with an industry tester, we realized
that there was no need for any extra handling code for the compliance
tests. The tests would run fine, if we only have a handling application.
However, in normal operation we wouldn't like the network to send us any
traffic on compliance testing port. To mitigate that, on the reception
path we filter out any traffic on compliance testing port if compliance
testing is not underway. User should define LORAWAN_COMPLIANCE_TEST macro
in mbed_app.json to enable traffic on compliance test port.
This commit fixes two bugs related to ADRAckReq:
- adr_ack_counter must be incremented for all uplink messages (not just confirmed)
- When ADR_ACK_LIMIT + ADR_ACK_DELAY has been reached, stack decreased used
datarate twice.
The length of a MAC command is not explicitly given and must be
implicitly known by the MAC implementation. Therefore unknown MAC
commands cannot be skipped and the first unknown MAC command
terminates the processing of the MAC command sequence.
This commit fixes the bug where MAC command processing was not
terminated when unknown MAC command was received.
When application requests link check request with add_link_check_request()
it was added to MAC command buffer. Again when actual TX was started,
stack cherry-picked the request into MAC buffer again resulting in a duplicate
entry in the buffer.
Functionality is changed now so that add_link_check_request() does not add
the request into MAC command buffer but it is cherry-picked into the buffer when
TX is issued.
set_next_channel() is the base function provided by LoRaPHY class and should be overridden
by the PHYs who behave differently as compared to EU868 like PHY layers.
CN470 PHY had been missing such an override.
In addition to that we have provided a parameter "fsb-mask-china" that can be used to
enforce a custom frequency sub-band of operation as most of the base stations in the market
may not support all 96 channels. Such a strategy will help in rapid network acquisition.
Users often use "show declaration" (or similar) in their IDE to see descriptions of callback
methods so the function descriptions should be placed close to function declaration itself.
This phy implementation was just to support a single sub-band in US region.
As we have decided to make FSBs configurable, we do not need this class anymore.
Just like US915 PHY, user can define a custom FSB mask for AU915 PHY.
This helps deployments where base stations do not portray full feature
channel sets and choose to stick with sub-bands.
Some LoRaMac methods were defined as public even though there were used only
internally.
Also removed definition of some methods which were not even implemented nor used.
- Duty cycle can be now only disabled with duty-cycle-on flag if region supports duty-cycle.
If region does not support duty-cycle, this flag has no effect and duty cycle is always
disabled.
- Also introduced a new flag (duty-cycle-on-join) to disable duty cycle for JOIN requests.
This flag can be used for testing only and is used to speed up JOIN request testing as
backoff times for JOIN request are really long (easily several minutes per attempt).
This flag works in conjunction with main duty cycle setting. Disabling duty-cycle-on-join
works only if duty-cycle-on is disabled (or region settings have duty cycle disabled).
In #b0b0261 we changed the RX2 data rate to start from the highest data rate
available for the PHY rather than standard defined DR.
This introduced a regression, i.e., even when somebody changed the default RX2 data
rate to something usable for their environment, it didn't take any effect. As in
reset_mac_params() we override the data rate with max value possible for that PHY.
This commit restores the original behaviour and we always use standard defined
values.
In release builds where MBED_ASSERT macro is syphoned off, we were hitting
an unused variable warning. To mitigate that we could direct the variable
used in MBED_ASSERT to void.
In order have a consistent return value for all methods in case of system is uninitialized
now also send and receive methods can return LORAWAN_STATUS_NOT_INITIALIZED.
Thix commit fixes a bug where stack was resending join-accept already
after RX1 if received join-response was invalid.
Stack should wait for RX2 before resending the join-accept.
LoRaMAC was not initialized properly if application called
connect(const lorawan_connect_t &connect);
This causes problems for example in case where application
first disconnects and then reconnects as counter values are not
initialized.
When node sends a CONFIRMED message and gateway sends ACK in RX1 window but the
message gets corrupted during the transmission (e.g. MIC fails), currently
our stack already checks for retransmission after RX1 and if retries attemps are
exhausted, TX_ERROR event is sent to application. This is wrong as MAC layer
will still attempt reception in RX2 window.
This commit fixes the behaviour so that TX_ERROR is not sent until RX2 window
has been closed.
It is quite possible that the user request for scheduling an uplink is deferred because of backoff or if it was a CONFIRMED message, a retry may take place on a different datarate and different channel.
We didn't have a hook for such deferred scheduling, telling the user whether the async rescheduling worked or not. This commit adds that capability and now we can tell the application if a scheduling failure took place after the original schedule request was accepted.
failed of its own accord) would prevent futher connect()'s due to the
CONN_IN_PROGRESS_FLAG remaining set. This change clears that flag in
the two cases described.
We had a bug especially in the reception path. Our recv window opening
delays were being calculated on the premise that the radio has to capture
5 preamble symbols out of 8 transmitted by the base station. However, in PHY
layer while setting radio rc settings, we were setting preamble length to be 8.
Preamble length register needs to be configured differently for Uplink and Downlink.
For uplink, we wish to transmit 8 preamble symbols whereas in the reception path we need
to receive 5 preamble symbols at least out of 8.
Alongwith that the maximum range of timing error may vary from platform to platform as it
is based upon the crystal in the chip. We have now made these parameters configurable and
have loaded them with the most optimal defaults.
The issue rose up when using ARMC6. A test case didn't initialize NetID
parameter for ABP while using connect(params) API. NetID is the first 7 bits
of the Device Address. It makes sense to actually remove the net-id parameter
from ABP settings as the stack can deduce it from device address. However, the ABP
structure is exposed in public APIs, so we can't really do that at the moment.
Simpler fix is to move the mask that helps us to extract first 7 bits of the device address
is exposed in lorawan_types.h and the user can use it to deduce correct net-id.
DR7 is used for FSK in AS932 region. As a default max DR, we should use a LoRa modulation
compatible data rate. Ofcourse if a device wishes to use FSK, it can set DR7 using set_data_rate() API
and turning off ADR, or an NS can configure a new channel for the device utilizing DR7.
The stack was trying to connect with default data rates which happened to be
the lowest data rates in a specific region. In the beginning device and NS do
not have agreed upon tx rx parameters and there can be synchronization issues.
When we use lower datarates, we may end up having a minute and a half long
transmissions that hnot only blocks the channel for a long time but also reduce
the chance of proper synch between device and NS. That's why we have decided to
begin with higher data rates and gradually decrease datarate if we do not hear
from the network server.
In the case when an automatic uplink was queued and the user do have something send,
we should give priority to user data instead od automatic uplink message.
This commit fixes some bugs from cancel_sending() method:
- System crashed if method was called before initialization.
Now LORAWAN_STATUS_NOT_INITIALIZED will be returned.
- Method returned LORAWAN_STATUS_BUSY error when no send request was pending.
LORAWAN_STATUS_OK should be returned in this case.
- LORAWAN_STATUS_BUSY is now returned if backoff timer is just about to be
dispatched (time_left returns 0).
51f92b0efd introduced
handling for connection attempts while a connection was already underway or have been
completed. Unfortunately a similar check slipped through and the stack was not able to continue
sending join requests if an error happened.
It was pointed out in #7432 and #7232 that the stack was comparing frame payload size
with the allowed payload size in a wrong manner in shcedule_tx().
We must strip the overhead from the frame before comparison.
We did have a similar check in prepare_ongoing_tx() API which would correctly analyse
the situation but a check was needed in schedule_tx() as well. The reason is that the
schedule_tx() API can be called automatically by the stack if the user intiated requested
was not promptly entertained because of duty cycle restriction. Now, the datarate can change
here (for CONFIRMED messages if the ack was not received after retries max out). That's why
a test for validity was needed.
We now perform a comparison using _ongoing_tx_message structure which contains the actual
FRMPayload size.
For proprietary type of messages only MHDR and Port field is used so we shouldn't add MAC commands
and other overhead into them.
In order to have consistent frame overhead, we have opted to always include Port field in the
frame.
For ABP: First call to connect() or connect(params) will return LORAWAN_STATUS_OK
and a CONNECTED event will be sent. Any subsequent call will return
LORAWAN_STATUS_ALREADY_CONNECTED (posix EISCONN) and no event is generated.
FOR OTAA: First call to connect() or connect(params) will return LORAWAN_STATUS_CONNECT_IN_PROGRESS
and a CONNECTED event will be sent whenever the JoinAccept is received. If the application
calls connect again before receiving the CONNECTED event, LORAWAN_STATUS_BUSY will be returned.
After the CONNECTED event is dispatched, any subsequent call to connect() or connect(params) API
will be returned with LORWAN_STATUS_ALREADY_CONNECTED.
No new parameters are accepted after the first call. The application must disconnect before making
a connect() call with new parameters.
This is a remedy for the issue #7230.
While the device is joining, LORAWAN_STATUS_CONNECT_IN_PROGRESS is returned.
However, if the device is already joined, we will return LORAWAN_STATUS_ALREADY_CONNECTED.
Instead of giving LoRaWANTimeHandler object as parameter for constructor,
object is now given via own initialize() method.
This change is needed for future refactoring where application can give own
PHY object for LoRa stack.
In rx_config(params) API we shouldn't check for radio state as radio may never get
idle for a class C device. That check made sense only for class A. As the PHY layer
have no conecpt of receive windows which is a MAC layer construct, we should remove the
state check.
The API will be changed later to void rx_config(params).
In addition to that another bug is fixed in the open_rx2_windows() API. We should set the rx slot
first before instantiating a test based on its value.
This commit fixes the issue reported in #7285.
If the radio is unable to transmit, its a fatal error and can happen
both while joining or sending a normal packet. In the case of such
a catastrophy we ought to tell the application that this happened.
A fix for the radio driver will also be patched.
receive(uint32_t) API in the LoRaRadio class (base class for the radio drivers) should
not take any argument as we decided to take hardware timers for RX timeout interrupts
instead of software timers. It is being refactored to receive(void).
This is an API change, but as it is not an application interface, we will not put a
deprecation notice. Only user of this API is our stack (LoRaPHY layer) which has been updated
accordingly.
Actual driver comes out of the tree and a PR is open there to update the drivers:
https://github.com/ARMmbed/mbed-semtech-lora-rf-drivers/pull/22
In addition to this an internal API belonging to LoRaPHY class is refactored.
set_rx_window(parameters) is refactored to handle_receive(void) which is more consistent with
handle_send().
If the automatic uplink is sent directly the call-stack becomes larger than 1K
which may cause serious problems in debug builds. Just to have a respite between
RX and TX we queue an event for the automatic uplink rather than directly undergoing
an automatic uplink.
RX1 and 2 delays needed to be more precise and aggregate tx time was
drifiting because of timing difference between actual tx interrupt and
our processing of that interrupt ever so slightly.
We now take a timestamp of the tx interrupt and take a time diff while
instantiating delay timers. The timestamp is then used to update the aggregate
tx time.
Two new methods are introduced in the LoRaMac class which provide current
timing and current receive slot. These functions are used by LoRaWANStack
for its processing.
If the value is an integer, the 4th bit is used for sign, so you can store
values upto 7 only whereas the datarate values could go upto 15. That's why
we need to turn this to an unsigned integer so that the last bit can also be used.
Travis astyle check pointed out some of the style mismatches in the code.
Not all of them are worth changing as they make the code unreadable and
some of them are semantically wrong.
So in this commit, we have attempted to pick the most important style
mismatches and rectify.
General stability improvements are performed.
A flag is added if a Class C RX2 window is open.
We shouldn't open it again if its already opened.
TX_CRYPTO_ERROR is renamed to CRYPTO_ERROR.
Keeping TX_CRYPTO_ERROR for backwards compatibility.
In Class C, rx timeout does not take place for RX2 windows, so if we have
not received anything, we would be retrying but if the no. of retries are
maxed out, and we have not recieved anything yet, we need a mechanism to
tell the upper layer that this has happened.
rx_abort() was sort of dead code as it was doing essentially nothing.
It might have actually meddled with the state machine if it was hit by
invoking on_ack_timeout_timer_event().
State machine and corresponding processors now take care of the ack timeout,
retries and all other bits, so we don't need abort_rx().
MCPS confirmation should be filled with the current number of retries
if the ack is not recieved for a CONFIRMED message.
Ack retry number needs to be incremented after the retry is made not before
that.
A few traces are added at the crucial junctions of the code just to tally with
the conceptual flow for debug purposes.
Application can use cancel_sending() API to stop any outstanding, outgoing
transmission (a TX which is not already queued for transmission). This can
potentially enable use cases where the application could cancel a transmission
and go to sleep if the backoff period is long enough rather than waiting for
the transmission to happen.
This API enables the application to get hold of remaining time after which
the transmission will take place. User can query the backoff time whenever
there is a packet in the TX pipe. If the event for the backoff expiry is
already queued, the stack does not provide backoff metadata.
An API is added to fetch any meta-data available after a succesful
transmission. The stack will make the meta data available after the
TX interrupt is processed. User can get the tx meta data after receiving
TX_DONE event.
Hasnain Virk
Martin Kojtal
Cruz Monrreal
Kimmo Vaisanen
Edd Inglis
Anna Bridge
Amanda Butler
Przemyslaw Stekiel