add battery reading

Author: HerrMuellerluedenscheid

examples/pico/src/main.rs

@@ -115,6 +115,10 @@ fn main() -> ! {
             .send_and_wait_reply(&at_command::power_saving_mode::GetPowerSavingMode {})
             .unwrap();
         info!("power_saving_mode: {}", power_saving_mode);
+        let battery_charge = modem
+            .send_and_wait_reply(&at_command::battery::BatteryCharge {})
+            .unwrap();
+        info!("battery_charge: {}", battery_charge);
         let gprs_status = modem
             .send_and_wait_reply(&at_command::at_cgatt::GPRSServiceStatus {})
             .unwrap();

src/at_command/battery.rs

@@ -0,0 +1,34 @@
+use crate::at_command::{AtRequest, AtResponse, BufferType};
+use crate::AtError;
+use at_commands::parser::CommandParser;
+
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+pub struct BatteryChargeStatus{
+    capacity_percent: i32,
+    voltage_millivolt: i32,
+}
+
+
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+pub struct BatteryCharge;
+
+impl AtRequest for BatteryCharge {
+    type Response = Result<(), AtError>;
+
+    fn get_command<'a>(&'a self, buffer: &'a mut BufferType) -> Result<&'a [u8], usize> {
+        at_commands::builder::CommandBuilder::create_execute(buffer, true)
+            .named("+CBC")
+            .finish()
+    }
+
+    fn parse_response(&self, data: &[u8]) -> Result<AtResponse, AtError> {
+        let (capacity_percent, voltage_millivolt) = CommandParser::parse(data)
+            .expect_identifier(b"\r\n+CBC: ")
+            .expect_int_parameter()
+            .expect_int_parameter()
+            .expect_identifier(b"\r\n\r\nOK")
+            .finish()?;
+        let status = BatteryChargeStatus{capacity_percent, voltage_millivolt};
+        Ok(AtResponse::BatteryCharge(status))
+    }
+}

src/at_command/mod.rs

@@ -10,6 +10,7 @@ use crate::at_command::sleep_indication::SleepIndication;
 use crate::{AtError, BUFFER_SIZE};
 #[cfg(feature = "defmt")]
 use defmt::debug;
+use crate::at_command::battery::BatteryChargeStatus;
 
 pub mod at;
 pub mod at_cgatt;
@@ -33,6 +34,7 @@ pub mod ntp;
 pub mod pdp_context;
 pub mod power_saving_mode;
 pub mod sleep_indication;
+pub mod battery;
 
 type BufferType = [u8; BUFFER_SIZE];
 
@@ -55,6 +57,7 @@ pub enum AtResponse {
     PDPContext(Option<(PDPState, i32)>),
     SleepIndication(SleepIndication),
     PowerSavingMode(PowerSavingModeState),
+    BatteryCharge(BatteryChargeStatus),
 }
 
 pub trait AtRequest {