3 unstable releases
0.1.1 | Apr 10, 2023 |
---|---|
0.1.0 | Apr 4, 2023 |
0.0.0 | Mar 21, 2023 |
#1528 in Embedded development
311 downloads per month
36KB
454 lines
defmt-brtt
: defmt over rtt
and bbq
, simultaneously!
This crate combines the functionality of defmt-rtt
and defmt-bbq
into one single crate.
This allows you to retrieve data over RTT, but also to pump it out over some other transport by reading the data from a bbqueue
.
Even if that is not a use-case you're interested in, you can also defmt-brtt
as an easier way of switching between using RTT and/or BBQueue as your defmt transport.
Features
rtt
: activate the RTT transport (works exactly likedefmt-rtt
, except for Buffer Size).bbq
: activate the BBQueue transport (works exactly likedefmt-bbq
, except for Buffer Size).async-await
: add a function todefmt_brtt::DefmtConsumer
that enables async-waiting for log data.
You must activate at least one of rtt
and bbq
.
Buffer Size
To configure the buffer size used by defmt-brtt
, you can set the environment variable DEFMT_BRTT_BUFFER_SIZE
to the desired size.
For example, if we'd want to use a 512 byte internal buffer, we would run DEFMT_BRTT_BUFFER_SIZE=512 cargo build
in the build directory of a project.
Note that defmt-brtt
assigned one buffer of size DEFMT_BRTT_BUFFER_SIZE
once for both rtt
and bbq
, if those features are activated.
User code required for use
To use the defmt
logger implementation provided by defmt-brtt
, you must always add insert the following use statement somewhere in your project:
use defmt_brtt as _;
rtt
To use the rtt
functionality of this crate, you only need to do is activate the rtt
feature (activated by default).
bbq
To use the bbq
functionality of this crate, you must activate the bbq
feature (activated by default). You must call defmt_brtt::init
and use the returned DefmtConsumer
to consume the defmt
data.
The data that is produced by the DefmtConsumer
can then be transported and fed to a decoder, such as defmt-print
, that will reconstruct the log messages from the defmt
data.
fn main() {
let logger = defmt_brtt::init();
loop {
if let Some(grant) = logger.read() {
let written_bytes = write_my_log_data_over_usb(&grant).ok();
// The step below is optional. Dropping the `Grant` releases
// all read bytes.
grant.release(written_bytes);
}
}
}
// If you have the `async-await` feature enabled, you
// can also do the following:
async fn read_logs(consumer: DefmtConsumer) {
loop {
let grant = logger.wait_for_log().await;
let written_bytes = write_my_log_data_over_usb(&grant).ok();
// The step below is optional. Dropping the `Grant` releases
// all read bytes.
grant.release(written_bytes);
}
}
Dependencies
~0.5–1MB
~23K SLoC