Add GST sentence parser

Cargo.toml

@@ -64,7 +64,7 @@ defmt-03 = ["dep:defmt", "heapless/defmt-03"]
 
 all-sentences = ["GNSS", "waypoint", "maritime", "water", "vendor-specific", "other"]
 # GNSS specific sentences related to the possition or speed relative to the ground
-GNSS = ["ALM", "GBS", "GGA", "GLL", "GNS", "GSA", "GSV", "RMC", "VTG"]
+GNSS = ["ALM", "GBS", "GGA", "GLL", "GNS", "GSA", "GST", "GSV", "RMC", "VTG"]
 
 waypoint = ["AAM", "BOD", "BWC", "BWW", "WNC", "ZFO", "ZTG"]
 maritime = ["waypoint", "water"]
@@ -116,6 +116,10 @@ GNS = []
 # feature: GNSS
 GSA = []
 
+# GST - GPS Pseudorange Noise Statistics
+# feature: GNSS
+GST = []
+
 # GSV - Satellites in view
 # feature: GNSS
 GSV = []

src/lib.rs

@@ -21,6 +21,7 @@
 //! - GLL *
 //! - GNS *
 //! - GSA *
+//! - GST
 //! - GSV *
 //! - HDT
 //! - MDA

src/parse.rs

@@ -118,6 +118,7 @@ pub enum ParseResult {
     GLL(GllData),
     GNS(GnsData),
     GSA(GsaData),
+    GST(GstData),
     GSV(GsvData),
     HDT(HdtData),
     MDA(MdaData),
@@ -150,6 +151,7 @@ impl From<&ParseResult> for SentenceType {
             ParseResult::GLL(_) => SentenceType::GLL,
             ParseResult::GNS(_) => SentenceType::GNS,
             ParseResult::GSA(_) => SentenceType::GSA,
+            ParseResult::GST(_) => SentenceType::GST,
             ParseResult::GSV(_) => SentenceType::GSV,
             ParseResult::HDT(_) => SentenceType::HDT,
             ParseResult::MDA(_) => SentenceType::MDA,
@@ -298,6 +300,15 @@ pub fn parse_str(sentence_input: &str) -> Result<ParseResult, Error> {
                     }
                 }
             }
+            SentenceType::GST => {
+                cfg_if! {
+                    if #[cfg(feature = "GST")] {
+                        parse_gst(nmea_sentence).map(ParseResult::GST)
+                    } else {
+                        return Err(Error::DisabledSentence);
+                    }
+                }
+            }
             SentenceType::GSV => {
                 cfg_if! {
                     if #[cfg(feature = "GSV")] {

src/parser.rs

@@ -374,6 +374,7 @@
             | ParseResult::BOD(_)
             | ParseResult::DBK(_)
             | ParseResult::GBS(_)
+            | ParseResult::GST(_)
             | ParseResult::AAM(_)
             | ParseResult::ALM(_)
             | ParseResult::HDT(_)
@@ -678,6 +679,7 @@
     /// - [`SentenceType::GGA`]
     /// - [`SentenceType::GNS`]
     /// - [`SentenceType::GSA`]
+    /// - [`SentenceType::GST`]
     /// - [`SentenceType::GSV`]
     ///
     /// ### Course

src/sentences/gst.rs

@@ -0,0 +1,137 @@
+use chrono::NaiveTime;
+
+use nom::{
+    character::complete::char,
+    number::complete::float,
+    combinator::opt,
+    IResult,
+};
+
+use crate::{parse::NmeaSentence, sentences::utils::parse_hms, Error, SentenceType};
+
+#[cfg(feature = "serde")]
+use serde::{Deserialize, Serialize};
+
+// GST - GPS Pseudorange Noise Statistics
+//
+//              1    2 3 4 5 6 7 8   9
+//              |    | | | | | | |   |
+// $ --GST,hhmmss.ss,x,x,x,x,x,x,x*hh<CR><LF>
+// 
+// Example: $GPGST,182141.000,15.5,15.3,7.2,21.8,0.9,0.5,0.8*54
+//
+// 1. UTC time of associated GGA fix
+// 2. Total RMS standard deviation of ranges inputs to the navigation solution
+// 3. Standard deviation (meters) of semi-major axis of error ellipse
+// 4. Standard deviation (meters) of semi-minor axis of error ellipse
+// 5. Orientation of semi-major axis of error ellipse (true north degrees)
+// 6. Standard deviation (meters) of latitude error
+// 7. Standard deviation (meters) of longitude error
+// 8. Standard deviation (meters) of altitude error
+// 9. Checksum
+// 
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+#[cfg_attr(feature = "defmt-03", derive(defmt::Format))]
+#[derive(Debug, PartialEq)]
+pub struct GstData {
+    #[cfg_attr(feature = "defmt-03", defmt(Debug2Format))]
+    pub time: Option<NaiveTime>,
+    pub rms_sd: Option<f32>,
+    pub ellipse_semi_major_sd: Option<f32>,
+    pub ellipse_semi_minor_sd: Option<f32>,
+    pub err_ellipse_orientation: Option<f32>,
+    pub lat_sd: Option<f32>,
+    pub long_sd: Option<f32>,
+    pub alt_sd: Option<f32>,
+}
+
+fn do_parse_gst(i: &str) -> IResult<&str, GstData> {
+    let (i, time) = opt(parse_hms)(i)?;
+    let (i,_) = char(',')(i)?;
+
+    let (i, rms_sd) = opt(float)(i)?;
+    let (i,_) = char(',')(i)?;
+
+    let (i, ellipse_semi_major_sd) = opt(float)(i)?;
+    let (i,_) = char(',')(i)?;
+
+    let (i, ellipse_semi_minor_sd) = opt(float)(i)?;
+    let (i,_) = char(',')(i)?;
+
+    let (i, err_ellipse_orientation) = opt(float)(i)?;
+    let (i,_) = char(',')(i)?;
+
+    let (i, lat_sd) = opt(float)(i)?;
+    let (i,_) = char(',')(i)?;
+
+    let (i, long_sd) = opt(float)(i)?;
+    let (i,_) = char(',')(i)?;
+
+    let (i, alt_sd) = opt(float)(i)?;
+
+    Ok((
+        i,
+        GstData {
+            time,
+            rms_sd,
+            ellipse_semi_major_sd,
+            ellipse_semi_minor_sd,
+            err_ellipse_orientation,
+            lat_sd,
+            long_sd,
+            alt_sd,
+        },
+    ))
+}
+pub fn parse_gst(sentence: NmeaSentence) -> Result<GstData, Error> {
+    if sentence.message_id != SentenceType::GST {
+        Err(Error::WrongSentenceHeader {
+            expected: SentenceType::GST,
+            found: sentence.message_id,
+        })
+    } else {
+        Ok(do_parse_gst(sentence.data)?.1)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::{parse::parse_nmea_sentence, Error};
+
+    fn run_parse_gst(line: &str) -> Result<GstData, Error> {
+        let s = parse_nmea_sentence(line).expect("GST sentence initial parse failed");
+        assert_eq!(s.checksum, s.calc_checksum());
+        parse_gst(s)
+    }
+
+    #[test]
+    fn test_parse_gst() {
+        assert_eq!(
+            GstData {
+                time: NaiveTime::from_hms_micro_opt(18, 21, 41, 00),
+                rms_sd: Some(15.5),
+                ellipse_semi_major_sd: Some(15.3),
+                ellipse_semi_minor_sd: Some(7.2),
+                err_ellipse_orientation: Some(21.8),
+                lat_sd: Some(0.9),
+                long_sd: Some(0.5),
+                alt_sd: Some(0.8),
+            },
+            run_parse_gst("$GPGST,182141.000,15.5,15.3,7.2,21.8,0.9,0.5,0.8*54").unwrap()
+        );
+        assert_eq!(
+            GstData {
+                time: None,
+                rms_sd: None,
+                ellipse_semi_major_sd: None,
+                ellipse_semi_minor_sd: None,
+                err_ellipse_orientation: None,
+                lat_sd: None,
+                long_sd: None,
+                alt_sd: None,
+            },
+            run_parse_gst("$GPGST,,,,,,,,*57").unwrap()
+        );
+    }
+}

src/sentences/mod.rs

@@ -11,6 +11,7 @@ pub mod gga;
 pub mod gll;
 pub mod gns;
 pub mod gsa;
+pub mod gst;
 pub mod gsv;
 pub mod hdt;
 pub mod mda;
@@ -47,6 +48,7 @@ pub use {
     gns::{parse_gns, GnsData},
     gnss_type::GnssType,
     gsa::{parse_gsa, GsaData},
+    gst::{parse_gst, GstData},
     gsv::{parse_gsv, GsvData},
     hdt::{parse_hdt, HdtData},
     mda::{parse_mda, MdaData},

tests/all_supported_messages.rs

@@ -21,6 +21,8 @@ fn test_all_supported_messages() {
         (SentenceType::GNS, "$GPGNS,224749.00,3333.4268304,N,11153.3538273,W,D,19,0.6,406.110,-26.294,6.0,0138,S,*46"),
         // GSA
         (SentenceType::GSA, "$GPGSA,A,3,23,31,22,16,03,07,,,,,,,1.8,1.1,1.4*3E"),
+        // GST
+        (SentenceType::GST, "$GPGST,182141.000,15.5,15.3,7.2,21.8,0.9,0.5,0.8*54"),
         // GSV
         (SentenceType::GSV, "$GPGSV,3,1,12,01,49,196,41,03,71,278,32,06,02,323,27,11,21,196,39*72"),
         // HDT