theoretically clean version which has been tested with and without the feature

Author: samchin

libs/cramium-hal/Cargo.toml

@@ -32,11 +32,13 @@ camera-ov2640 = []
 camera-gc2145 = []
 display-sh1107 = []
 axp2101 = []
+bmp180 = []
 board-baosec = [
     "std",
     "camera-gc2145",
     "display-sh1107",
     "axp2101",
+    "bmp180",
     "utralib/cramium-soc",
     "ux-api/board-baosec",
 ] # USB form factor token
@@ -45,6 +47,7 @@ loader-baosec = [
     "camera-gc2145",
     "display-sh1107",
     "axp2101",
+    "bmp180",
     "ux-api/loader-baosec",
 ]
 kernel-baosec = ["utralib/cramium-soc"]

libs/cramium-hal/src/bmp180.rs

@@ -1,15 +1,14 @@
 use cramium_api::{I2cApi, I2cResult};
 
 pub const BMP180_ADDR: u8 = 0x77;
-#[cfg(feature = "std")]
 const REG_CALIB_START: u8 = 0xAA;
 const REG_CTRL: u8 = 0xF4;
 const REG_DATA_START: u8 = 0xF6;
 const CMD_READ_TEMP: u8 = 0x2E;
+const REG_CHIP_ID: u8 = 0xD0;
 
 #[derive(Debug, Clone, Copy)]
 
-#[allow(dead_code)]
 struct Bmp180Calibration {
     ac1: i16,
     ac2: i16,
@@ -29,10 +28,17 @@ pub struct Bmp180 {
 }
 
 impl Bmp180 {
-    #[cfg(feature = "std")]
     pub fn new(i2c: &mut dyn I2cApi) -> Result<Self, I2cResult> {
-        let mut cal_buf = [0u8; 22];
+        // dummy read to wake the chip
+        let mut chip_id_buf = [0u8; 1];
+        match i2c.i2c_read(BMP180_ADDR, REG_CHIP_ID, &mut chip_id_buf, true) {
+            Ok(I2cResult::Ack(_)) => (),
+            Ok(I2cResult::Nack) => (),
+            Ok(other) => return Err(other),
+            Err(_) => return Err(I2cResult::InternalError),
+        }
 
+        let mut cal_buf = [0u8; 22];
         match i2c.i2c_read(BMP180_ADDR, REG_CALIB_START, &mut cal_buf, true) {
             Ok(i2c_result) => match i2c_result {
                 I2cResult::Ack(_) => (),

libs/cramium-hal/src/lib.rs

@@ -5,6 +5,7 @@
 pub mod debug;
 #[cfg(feature = "axp2101")]
 pub mod axp2101;
+#[cfg(feature = "bmp180")]
 pub mod bmp180;
 pub mod board;
 #[cfg(feature = "camera-gc2145")]

services/bao-console/Cargo.toml

@@ -49,6 +49,10 @@ hosted-baosec = [
     "pddb/hosted-baosec",
     "cramium-hal/hosted-baosec",
 ]
+bmp180 = [
+    "cramium-hal/bmp180",
+    "cram-hal-service",
+]
 usb = []
 battery-readout = []
 with-pddb = []

services/bao-console/src/cmds/test.rs

@@ -1,6 +1,4 @@
 use String;
-use cram_hal_service::I2c;
-use cramium_hal::bmp180::Bmp180;
 
 use crate::{CommonEnv, ShellCmdApi};
 
@@ -15,13 +13,22 @@ impl<'a> ShellCmdApi<'a> for Test {
     fn process(&mut self, args: String, _env: &mut CommonEnv) -> Result<Option<String>, xous::Error> {
         use core::fmt::Write;
         let mut ret = String::new();
+
+        #[allow(unused_variables)]
         let helpstring = "Test commands. See code for options.";
 
+        #[cfg(feature = "bmp180")]
+        let helpstring = "Usage:
+        temp     - reads temperature from bmp180.";
+
         let mut tokens = args.split(' ');
 
         if let Some(sub_cmd) = tokens.next() {
             match sub_cmd {
+                #[cfg(feature = "bmp180")]
                 "temp" => {
+                    use cram_hal_service::I2c;
+                    use cramium_hal::bmp180::Bmp180;
                     let mut i2c = I2c::new();
 
                     match Bmp180::new(&mut i2c) {

services/cram-hal-service/Cargo.toml

@@ -45,6 +45,7 @@ rawserial = []
 pinger = []
 swap = []
 mpw = ["cramium-hal/mpw"]
+bmp180 = ["cramium-hal/bmp180"]
 board-baosec = ["cramium-hal/board-baosec"]
 board-baosor = ["cramium-hal/board-baosor"]
 board-dabao = ["cramium-hal/board-dabao"]