lots of fixes

.gitignore

@@ -1,3 +1,3 @@
 
 /build
-
+/.cache

.gitmodules

@@ -1,3 +1,3 @@
-[submodule "libs/pico-sdk"]
+[submodule "libs/adafruitGFX"]
-	path = libs/pico-sdk
+	path = libs/adafruitGFX
-	url = https://github.com/raspberrypi/pico-sdk.git
+	url = https://git.gay/LailaTheElf/AdafruitGFX-RaspberryPICO.git

.vscode/launch.json

@@ -0,0 +1,52 @@
+{
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Pico Debug (Cortex-Debug)",
+            "cwd": "/usr/shere/openocd/scripts",
+            "type": "cortex-debug",
+            "executable": "${command:cmake.launchTargetPath}",
+            "request": "launch",
+            "servertype": "openocd",
+            // "serverpath": "${userHome}/.pico-sdk/openocd/0.12.0+dev/openocd.exe",
+            // "gdbPath": "${command:raspberry-pi-pico.getGDBPath}",
+            "gdbPath": "/usr/bin/arm-none-eabi-gdb",
+            "device": "RP2040",
+            "configFiles": [
+                "interface/cmsis-dap.cfg",
+                "target/rp2040.cfg"
+            ],
+            "svdFile": "${PICO_SDK_PATH}/src/rp2040/hardware_regs/RP2040.svd",
+            "runToEntryPoint": "main",
+            // Fix for no_flash binaries, where monitor reset halt doesn't do what is expected
+            // Also works fine for flash binaries
+            "overrideLaunchCommands": [
+                "monitor reset init",
+                "load \"${command:cmake.launchTargetPath}\""
+            ],
+            "openOCDLaunchCommands": [
+                "adapter speed 5000"
+            ]
+        },
+        {
+            "name": "Pico Debug (Cortex-Debug with external OpenOCD)",
+            "cwd": "${workspaceRoot}",
+            "type": "cortex-debug",
+            "executable": "${command:cmake.launchTargetPath}",
+            "request": "launch",
+            "servertype": "external",
+            "gdbTarget": "localhost:3333",
+            // "gdbPath": "${command:raspberry-pi-pico.getGDBPath}",
+            "gdbPath": "/usr/bin/arm-none-eabi-gdb",
+            "device": "RP2040",
+            "svdFile": "${PICO_SDK_PATH}/src/rp2040/hardware_regs/RP2040.svd",
+            "runToEntryPoint": "main",
+            // Fix for no_flash binaries, where monitor reset halt doesn't do what is expected
+            // Also works fine for flash binaries
+            "overrideLaunchCommands": [
+                "monitor reset init",
+                "load \"${command:cmake.launchTargetPath}\""
+            ]
+        },
+    ]
+}

CMakeLists.txt

@@ -1,21 +1,31 @@
 cmake_minimum_required(VERSION 3.13)
 
-# initialize the SDK based on PICO_SDK_PATH
+set(PICO_SDK_PATH $ENV{PICO_SDK_PATH})
-# note: this must happen before project()
+include(pico_sdk_import.cmake)
-include(libs/pico-sdk/pico_sdk_init.cmake)
 
+project(temp_sensor_debug)
 project(temp_sensor)
 
-# initialize the Raspberry Pi Pico SDK
 pico_sdk_init()
 
-add_executable(my_project
+add_subdirectory(libs/adafruitGFX/AdafruitGFXPico)
-    src/main.c
+
-    src/max31856.c
+add_executable(temp_sensor_debug
+    src/main.cpp
+    src/max31856.cpp
 )
 
-# Add pico_stdlib library which aggregates commonly used features
+target_link_libraries(temp_sensor_debug pico_stdlib hardware_spi AdafruitGFXPico)
-target_link_libraries(my_project pico_stdlib hardware_spi)
+target_compile_options(temp_sensor_debug PRIVATE -Og)
+pico_enable_stdio_usb(temp_sensor_debug 1)
+pico_enable_stdio_uart(temp_sensor_debug 0)
 
-# create map/bin/hex/uf2 file in addition to ELF.
+add_executable(temp_sensor
-pico_add_extra_outputs(my_project)
+    src/main.cpp
+    src/max31856.cpp
+)
+
+target_link_libraries(temp_sensor pico_stdlib hardware_spi AdafruitGFXPico)
+target_compile_options(temp_sensor PRIVATE -Ofast)
+pico_enable_stdio_usb(temp_sensor 1)
+pico_enable_stdio_uart(temp_sensor 0)

pico_sdk_import.cmake

@@ -0,0 +1,121 @@
+# This is a copy of <PICO_SDK_PATH>/external/pico_sdk_import.cmake
+
+# This can be dropped into an external project to help locate this SDK
+# It should be include()ed prior to project()
+
+# Copyright 2020 (c) 2020 Raspberry Pi (Trading) Ltd.
+#
+# Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
+# following conditions are met:
+#
+# 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following
+# disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
+# disclaimer in the documentation and/or other materials provided with the distribution.
+#
+# 3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products
+# derived from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+# INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+if (DEFINED ENV{PICO_SDK_PATH} AND (NOT PICO_SDK_PATH))
+    set(PICO_SDK_PATH $ENV{PICO_SDK_PATH})
+    message("Using PICO_SDK_PATH from environment ('${PICO_SDK_PATH}')")
+endif ()
+
+if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT} AND (NOT PICO_SDK_FETCH_FROM_GIT))
+    set(PICO_SDK_FETCH_FROM_GIT $ENV{PICO_SDK_FETCH_FROM_GIT})
+    message("Using PICO_SDK_FETCH_FROM_GIT from environment ('${PICO_SDK_FETCH_FROM_GIT}')")
+endif ()
+
+if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT_PATH} AND (NOT PICO_SDK_FETCH_FROM_GIT_PATH))
+    set(PICO_SDK_FETCH_FROM_GIT_PATH $ENV{PICO_SDK_FETCH_FROM_GIT_PATH})
+    message("Using PICO_SDK_FETCH_FROM_GIT_PATH from environment ('${PICO_SDK_FETCH_FROM_GIT_PATH}')")
+endif ()
+
+if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT_TAG} AND (NOT PICO_SDK_FETCH_FROM_GIT_TAG))
+    set(PICO_SDK_FETCH_FROM_GIT_TAG $ENV{PICO_SDK_FETCH_FROM_GIT_TAG})
+    message("Using PICO_SDK_FETCH_FROM_GIT_TAG from environment ('${PICO_SDK_FETCH_FROM_GIT_TAG}')")
+endif ()
+
+if (PICO_SDK_FETCH_FROM_GIT AND NOT PICO_SDK_FETCH_FROM_GIT_TAG)
+  set(PICO_SDK_FETCH_FROM_GIT_TAG "master")
+  message("Using master as default value for PICO_SDK_FETCH_FROM_GIT_TAG")
+endif()
+
+set(PICO_SDK_PATH "${PICO_SDK_PATH}" CACHE PATH "Path to the Raspberry Pi Pico SDK")
+set(PICO_SDK_FETCH_FROM_GIT "${PICO_SDK_FETCH_FROM_GIT}" CACHE BOOL "Set to ON to fetch copy of SDK from git if not otherwise locatable")
+set(PICO_SDK_FETCH_FROM_GIT_PATH "${PICO_SDK_FETCH_FROM_GIT_PATH}" CACHE FILEPATH "location to download SDK")
+set(PICO_SDK_FETCH_FROM_GIT_TAG "${PICO_SDK_FETCH_FROM_GIT_TAG}" CACHE FILEPATH "release tag for SDK")
+
+if (NOT PICO_SDK_PATH)
+    if (PICO_SDK_FETCH_FROM_GIT)
+        include(FetchContent)
+        set(FETCHCONTENT_BASE_DIR_SAVE ${FETCHCONTENT_BASE_DIR})
+        if (PICO_SDK_FETCH_FROM_GIT_PATH)
+            get_filename_component(FETCHCONTENT_BASE_DIR "${PICO_SDK_FETCH_FROM_GIT_PATH}" REALPATH BASE_DIR "${CMAKE_SOURCE_DIR}")
+        endif ()
+        FetchContent_Declare(
+                pico_sdk
+                GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
+                GIT_TAG ${PICO_SDK_FETCH_FROM_GIT_TAG}
+        )
+
+        if (NOT pico_sdk)
+            message("Downloading Raspberry Pi Pico SDK")
+            # GIT_SUBMODULES_RECURSE was added in 3.17
+            if (${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.17.0")
+                FetchContent_Populate(
+                        pico_sdk
+                        QUIET
+                        GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
+                        GIT_TAG ${PICO_SDK_FETCH_FROM_GIT_TAG}
+                        GIT_SUBMODULES_RECURSE FALSE
+
+                        SOURCE_DIR ${FETCHCONTENT_BASE_DIR}/pico_sdk-src
+                        BINARY_DIR ${FETCHCONTENT_BASE_DIR}/pico_sdk-build
+                        SUBBUILD_DIR ${FETCHCONTENT_BASE_DIR}/pico_sdk-subbuild
+                )
+            else ()
+                FetchContent_Populate(
+                        pico_sdk
+                        QUIET
+                        GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
+                        GIT_TAG ${PICO_SDK_FETCH_FROM_GIT_TAG}
+
+                        SOURCE_DIR ${FETCHCONTENT_BASE_DIR}/pico_sdk-src
+                        BINARY_DIR ${FETCHCONTENT_BASE_DIR}/pico_sdk-build
+                        SUBBUILD_DIR ${FETCHCONTENT_BASE_DIR}/pico_sdk-subbuild
+                )
+            endif ()
+
+            set(PICO_SDK_PATH ${pico_sdk_SOURCE_DIR})
+        endif ()
+        set(FETCHCONTENT_BASE_DIR ${FETCHCONTENT_BASE_DIR_SAVE})
+    else ()
+        message(FATAL_ERROR
+                "SDK location was not specified. Please set PICO_SDK_PATH or set PICO_SDK_FETCH_FROM_GIT to on to fetch from git."
+                )
+    endif ()
+endif ()
+
+get_filename_component(PICO_SDK_PATH "${PICO_SDK_PATH}" REALPATH BASE_DIR "${CMAKE_BINARY_DIR}")
+if (NOT EXISTS ${PICO_SDK_PATH})
+    message(FATAL_ERROR "Directory '${PICO_SDK_PATH}' not found")
+endif ()
+
+set(PICO_SDK_INIT_CMAKE_FILE ${PICO_SDK_PATH}/pico_sdk_init.cmake)
+if (NOT EXISTS ${PICO_SDK_INIT_CMAKE_FILE})
+    message(FATAL_ERROR "Directory '${PICO_SDK_PATH}' does not appear to contain the Raspberry Pi Pico SDK")
+endif ()
+
+set(PICO_SDK_PATH ${PICO_SDK_PATH} CACHE PATH "Path to the Raspberry Pi Pico SDK" FORCE)
+
+include(${PICO_SDK_INIT_CMAKE_FILE})

src/main.c

@@ -1,65 +0,0 @@
-#include <stdio.h>
-#include "pico/stdlib.h"
-
-#include "max31856.h"
-
-// pin rgb led on Seeed XIAO RP2040
-#define PIN_RGB_R 17
-#define PIN_RGB_G 16
-#define PIN_RGB_B 25
-
-max31856_t temp[2];
-
-void init_rbg()
-{
-  gpio_init(PIN_RGB_R);
-  gpio_set_dir(PIN_RGB_R, GPIO_OUT);
-  gpio_init(PIN_RGB_G);
-  gpio_set_dir(PIN_RGB_G, GPIO_OUT);
-  gpio_init(PIN_RGB_B);
-  gpio_set_dir(PIN_RGB_B, GPIO_OUT);
-}
-
-void rgb_rainbow()
-{
-  gpio_put(PIN_RGB_G, 1);
-  sleep_ms(250);
-  gpio_put(PIN_RGB_R, 0);
-  sleep_ms(250);
-  gpio_put(PIN_RGB_B, 1);
-  sleep_ms(250);
-  gpio_put(PIN_RGB_G, 0);
-  sleep_ms(250);
-  gpio_put(PIN_RGB_R, 1);
-  sleep_ms(250);
-  gpio_put(PIN_RGB_B, 0);
-  sleep_ms(250);
-  gpio_put(PIN_RGB_R, 0);
-}
-
-int main() {
-  setup_default_uart();
-  printf("Hello, world!\n");
-
-  init_rbg();
-  rgb_rainbow();
-
-  // init temp sensors
-  temp[0].pin_cs = 4;
-  max31856_init(&(temp[0]));
-  temp[1].pin_cs = 5;
-  max31856_init(&(temp[1]));
-  // config temp sensor 0
-  max31856_write8(&(temp[0]), MAX31856_REG_CR0, MAX31856_REG_CR0_CMODE | /*MAX31856_REG_CR0_OCFAULT |*/ MAX31856_REG_CR0_50HZ);
-  max31856_write8(&(temp[0]), MAX31856_REG_CR1, MAX31856_REG_CR1_AVGSEL_1 | MAX31856_REG_CR1_TC_TYPE_K);
-  // config temp sensor 1
-  max31856_write8(&(temp[1]), MAX31856_REG_CR0, MAX31856_REG_CR0_CMODE | /*MAX31856_REG_CR0_OCFAULT |*/ MAX31856_REG_CR0_50HZ);
-  max31856_write8(&(temp[1]), MAX31856_REG_CR1, MAX31856_REG_CR1_AVGSEL_1 | MAX31856_REG_CR1_TC_TYPE_K);
-
-  while (true)
-  {
-    rgb_rainbow();
-  }
-  return 0;
-}
-

src/main.cpp

@@ -0,0 +1,111 @@
+#include <cstdint>
+#include <pico/time.h>
+#include <stdio.h>
+#include <pico/stdlib.h>
+#include <Adafruit_SSD1306.h>
+#include <Adafruit_SPIDevice.h>
+#include <Adafruit_ILI9341.h>
+
+#include "max31856.h"
+
+// pin rgb led on Seeed XIAO RP2040
+#define PIN_RGB_R 17
+#define PIN_RGB_G 16
+#define PIN_RGB_B 25
+
+#define PIN_SPI_CLK 2
+#define PIN_SPI_MISO 4
+#define PIN_SPI_MOSI 3
+#define PIN_MAX31856_CS 1
+#define PIN_DISPLAY_CS 0
+#define PIN_DISPLAY_DC 7
+#define PIN_DISPLAY_RST 6
+
+max31856_t temp[2];
+Adafruit_SPIDevice spidev(PIN_DISPLAY_CS, PIN_SPI_CLK, PIN_SPI_MISO, PIN_SPI_MOSI);
+Adafruit_SSD1306 display(128, 64, &spidev, PIN_DISPLAY_DC, PIN_DISPLAY_RST, PIN_DISPLAY_CS);
+
+void init_rbg()
+{
+  gpio_init(PIN_RGB_R);
+  gpio_set_dir(PIN_RGB_R, GPIO_OUT);
+  gpio_init(PIN_RGB_G);
+  gpio_set_dir(PIN_RGB_G, GPIO_OUT);
+  gpio_init(PIN_RGB_B);
+  gpio_set_dir(PIN_RGB_B, GPIO_OUT);
+}
+
+void rgb_rainbow()
+{
+  gpio_put(PIN_RGB_G, 1);
+  sleep_ms(250);
+  gpio_put(PIN_RGB_R, 0);
+  sleep_ms(250);
+  gpio_put(PIN_RGB_B, 1);
+  sleep_ms(250);
+  gpio_put(PIN_RGB_G, 0);
+  sleep_ms(250);
+  gpio_put(PIN_RGB_R, 1);
+  sleep_ms(250);
+  gpio_put(PIN_RGB_B, 0);
+  sleep_ms(250);
+}
+
+int main() {
+  stdio_init_all();
+  init_rbg();
+
+  display.begin();
+
+  // init temp sensors
+  temp[0].pin_cs = PIN_MAX31856_CS;
+  max31856_init(&(temp[0]));
+  gpio_set_function(PIN_SPI_CLK, GPIO_FUNC_SPI);
+  gpio_set_function(PIN_SPI_MOSI, GPIO_FUNC_SPI);
+  gpio_set_function(PIN_SPI_MISO, GPIO_FUNC_SPI);
+  // temp[1].pin_cs = 5;
+  //max31856_init(&(temp[1]));
+  // config temp sensor 0
+  max31856_write8(&(temp[0]), MAX31856_REG_CR0, MAX31856_REG_CR0_CMODE | /*MAX31856_REG_CR0_OCFAULT |*/ MAX31856_REG_CR0_50HZ);
+  max31856_write8(&(temp[0]), MAX31856_REG_CR1, MAX31856_REG_CR1_AVGSEL_4 | MAX31856_REG_CR1_TC_TYPE_K);
+  // config temp sensor 1
+  //max31856_write8(&(temp[1]), MAX31856_REG_CR0, MAX31856_REG_CR0_CMODE | /*MAX31856_REG_CR0_OCFAULT |*/ MAX31856_REG_CR0_50HZ);
+  //max31856_write8(&(temp[1]), MAX31856_REG_CR1, MAX31856_REG_CR1_AVGSEL_1 | MAX31856_REG_CR1_TC_TYPE_K);
+
+  display.fillScreen(SSD1306_BLACK);
+  display.setTextColor(SSD1306_WHITE);
+  display.setTextSize(2);
+  display.display();
+
+  rgb_rainbow();
+
+  while (true)
+  {
+    char cj_str[8];
+    char tc_str[8];
+
+    spi_set_format(SPI_MAX31856, SPI_MAX31856_BLOCK_SIZE, SPI_MAX31856_SPO, SPI_MAX31856_SPH, SPI_MAX31856_BIT_ORDER);
+    sleep_ms(5);
+    max31856_temp_t cj = max31856_get_cj_temp_c(&temp[0]);
+    snprintf(&cj_str[0], 8, "%i.%02uC", cj.i, cj.f);
+    max31856_temp_t tc = max31856_get_tc_temp_c(&temp[0]);
+    snprintf(&tc_str[0], 8, "%i.%02uC", tc.i, tc.f);
+
+    printf("CJ temp: %s\n", &cj_str[0]);
+    printf("TC temp: %s\n", &tc_str[0]);
+
+    spi_set_format(spi0, 8, SPI_CPOL_0, SPI_CPHA_0, SPI_MSB_FIRST);
+    sleep_ms(5);
+    display.fillScreen(SSD1306_BLACK);
+    display.setCursor(0, 0);
+    display.print("CJ ");
+    display.println(&cj_str[0]);
+    display.print("TC ");
+    display.println(&tc_str[0]);
+    display.display();
+
+    sleep_ms(200);
+  }
+  return 0;
+}
+

src/max31856.c

@@ -1,78 +0,0 @@
-#include "pico/stdlib.h"
-#include "hardware/spi.h"
-#include <stdint.h>
-
-#include "max31856.h"
-
-// max31856 pins
-#define SPI_MAX31856            spi0
-#define SPI_MAX31856_BOUD       1E6 // 1 MHz (max31856 can go up to 5 MHz)
-#define SPI_MAX31856_SPO        SPI_CPOL_0
-#define SPI_MAX31856_SPH        SPI_CPHA_1
-#define SPI_MAX31856_BIT_ORDER  SPI_MSB_FIRST
-#define SPI_MAX31856_BLOCK_SIZE 8
-
-void max31856_init(max31856_t *max)
-{
-   // init GPIO for CS
-   gpio_init(max->pin_cs);
-   gpio_set_dir(max->pin_cs, GPIO_OUT);
-   gpio_put(max->pin_cs, 1);
-
-   // init SPI
-   spi_init(SPI_MAX31856, SPI_MAX31856_BOUD);
-   spi_set_format(SPI_MAX31856, SPI_MAX31856_BLOCK_SIZE, SPI_MAX31856_SPO, SPI_MAX31856_SPH, SPI_MAX31856_BIT_ORDER);
-
-   max->initilzed = true;
-}
-
-void max31856_deinit(max31856_t *max)
-{
-   max->initilzed = false;
-   spi_deinit(SPI_MAX31856);
-   gpio_deinit(max->pin_cs);
-}
-
-int max31856_write8(max31856_t *max, uint8_t addr, uint8_t value)
-{
-   if (!(max->initilzed))
-   {
-      return -1;
-   }
-   const uint8_t buff[2] = {addr | 0x80, value};
-   gpio_put(max->pin_cs, 0);
-   spi_write_blocking(SPI_MAX31856, &buff[0], 2);
-   gpio_put(max->pin_cs, 1);
-
-   return 0;
-}
-
-uint8_t max31856_read8(max31856_t *max, uint8_t addr)
-{
-   if (!(max->initilzed))
-   {
-      return -1;
-   }
-   const uint16_t buff_tx = (addr & 0x7F)<<8;
-   const uint8_t buff_rx[] = {0, 0};
-   gpio_put(max->pin_cs, 0);
-   spi_read_blocking(SPI_MAX31856, buff_tx, &buff_rx[0], 2);
-   gpio_put(max->pin_cs, 1);
-
-   return buff_rx[1];
-}
-
-uint16_t max31856_read16(max31856_t *max, uint8_t addr)
-{
-   if (!(max->initilzed))
-   {
-      return -1;
-   }
-   const uint16_t buff_tx = (addr & 0x7F)<<8;
-   const uint8_t buff_rx[] = {0, 0, 0};
-   gpio_put(max->pin_cs, 0);
-   spi_read_blocking(SPI_MAX31856, buff_tx, &buff_rx[0], 3);
-   gpio_put(max->pin_cs, 1);
-
-   return buff_rx[1]<<8 | buff_rx[2];
-}

src/max31856.cpp

@@ -0,0 +1,131 @@
+#include "pico/stdlib.h"
+#include "hardware/spi.h"
+#include <cstdint>
+#include <stdint.h>
+
+#include "max31856.h"
+
+void max31856_init(max31856_t *max)
+{
+   // init GPIO for CS
+   gpio_init(max->pin_cs);
+   gpio_set_dir(max->pin_cs, GPIO_OUT);
+   gpio_put(max->pin_cs, 1);
+
+   // init SPI
+   spi_init(SPI_MAX31856, SPI_MAX31856_BOUD);
+   spi_set_format(SPI_MAX31856, SPI_MAX31856_BLOCK_SIZE, SPI_MAX31856_SPO, SPI_MAX31856_SPH, SPI_MAX31856_BIT_ORDER);
+
+   max->initilzed = true;
+}
+
+void max31856_deinit(max31856_t *max)
+{
+   max->initilzed = false;
+   spi_deinit(SPI_MAX31856);
+   gpio_deinit(max->pin_cs);
+}
+
+int max31856_write8(max31856_t *max, uint8_t addr, uint8_t value)
+{
+   if (!(max->initilzed))
+   {
+      return -1;
+   }
+   uint8_t buff[2] = {addr | 0x80, value};
+   gpio_put(max->pin_cs, 0);
+   spi_write_blocking(SPI_MAX31856, &buff[0], 2);
+   gpio_put(max->pin_cs, 1);
+
+   return 0;
+}
+
+uint8_t max31856_read8(max31856_t *max, uint8_t addr)
+{
+   if (!(max->initilzed))
+   {
+      return -1;
+   }
+   uint8_t buff_tx = addr & 0x7F;
+   uint8_t buff_rx[] = {0, 0};
+   gpio_put(max->pin_cs, 0);
+   spi_read_blocking(SPI_MAX31856, buff_tx, &buff_rx[0], 2);
+   gpio_put(max->pin_cs, 1);
+
+   return buff_rx[1];
+}
+
+uint16_t max31856_read16(max31856_t *max, uint8_t addr)
+{
+   if (!(max->initilzed))
+   {
+      return -1;
+   }
+   uint8_t buff_tx = addr & 0x7F;
+   uint8_t buff_rx[] = {0, 0, 0};
+   gpio_put(max->pin_cs, 0);
+   spi_read_blocking(SPI_MAX31856, buff_tx, &buff_rx[0], 3);
+   gpio_put(max->pin_cs, 1);
+
+   return buff_rx[1]<<8 | buff_rx[2];
+}
+
+uint32_t max31856_read24(max31856_t *max, uint8_t addr)
+{
+   if (!(max->initilzed))
+   {
+      return -1;
+   }
+   uint8_t buff_tx = addr & 0x7F;
+   uint8_t buff_rx[] = {0, 0, 0, 0};
+   gpio_put(max->pin_cs, 0);
+   spi_read_blocking(SPI_MAX31856, buff_tx, &buff_rx[0], 4);
+   gpio_put(max->pin_cs, 1);
+
+   return 0 | buff_rx[1]<<16 | buff_rx[2]<<8 | buff_rx[3];
+}
+
+max31856_temp_t max31856_convert_cj_temp_c(uint16_t row) {
+   bool negarive = ((row & 0x8000) == 0) ? false : true;
+   if (negarive) {
+      row = (~row) + 1;
+   }
+
+   max31856_temp_t temp = {
+      (int16_t)(row >> 8),
+      (uint8_t)(((row & 0xFF)*100)/256)
+   };
+
+   if (negarive) {
+      temp.i = -temp.i;
+   }
+
+   return temp;
+}
+
+max31856_temp_t max31856_convert_tc_temp_c(uint32_t row) {
+   bool negarive = ((row & 0x800000) == 0) ? false : true;
+   if (negarive) {
+      row = (row^0xFFFFFF) + 1;
+   }
+   row &= 0xFFFFFF;
+
+   max31856_temp_t temp = {
+      (int16_t)(row >> 12),
+      (uint8_t)(((row & 0xFFF)*100)/0x1000)
+   };
+
+   if (negarive) {
+      temp.i = -temp.i;
+   }
+
+   return temp;
+}
+
+max31856_temp_t max31856_get_cj_temp_c(max31856_t *max) {
+   return max31856_convert_cj_temp_c(max31856_read16(max, MAX31856_REG_CJTH));
+}
+
+max31856_temp_t max31856_get_tc_temp_c(max31856_t *max) {
+   return max31856_convert_tc_temp_c(max31856_read24(max, MAX31856_REG_LTCBH));
+}

src/max31856.h

@@ -1,6 +1,7 @@
 #ifndef MAX31856_H
 #define MAX31856_H
 
+#include <cstdint>
 #include <stdint.h>
 
 typedef struct max31856_s {
@@ -9,46 +10,68 @@ typedef struct max31856_s {
   bool autoDeinit;
 } max31856_t;
 
+typedef struct max31856_temp_s {
+  int16_t i;
+  uint8_t f;
+} max31856_temp_t;
+
 void max31856_init(max31856_t *max);
 void max31856_deinit(max31856_t *max);
 int max31856_write8(max31856_t *max, uint8_t addr, uint8_t value);
 uint16_t max31856_read16(max31856_t *max, uint8_t addr);
+uint32_t max31856_read24(max31856_t *max, uint8_t addr);
+max31856_temp_t max31856_convert_cj_temp_c(uint16_t row);
+max31856_temp_t max31856_convert_tc_temp_c(uint32_t row);
+max31856_temp_t max31856_get_cj_temp_c(max31856_t *max);
+max31856_temp_t max31856_get_tc_temp_c(max31856_t *max);
 
-#define MAX31856_REG_CR0    0x00
+#define MAX31856_REG_CR0   ((uint8_t)0x00)
-#define MAX31856_REG_CR0_CMODE      0x80
+#define MAX31856_REG_CR0_CMODE      ((uint8_t)0x80) // convertion mode
-#define MAX31856_REG_CR0_1SHOT      0x40
+#define MAX31856_REG_CR0_1SHOT      ((uint8_t)0x40) // one-shot mode
-#define MAX31856_REG_CR0_OCFAULT    0x10
+#define MAX31856_REG_CR0_OCFAULT    ((uint8_t)0x30) // open-circuit fault detection
-#define MAX31856_REG_CR0_JC         0x08
+#define MAX31856_REG_CR0_JC         ((uint8_t)0x08) // cold-junction sensor disable
-#define MAX31856_REG_CR0_FAULT      0x04
+#define MAX31856_REG_CR0_FAULT      ((uint8_t)0x04) // fault mode
-#define MAX31856_REG_CR0_FAULTCLR   0x02
+#define MAX31856_REG_CR0_FAULTCLR   ((uint8_t)0x02) // foult status clear
-#define MAX31856_REG_CR0_50HZ       0x01
+#define MAX31856_REG_CR0_50HZ       ((uint8_t)0x01) // 50Hz/60Hz node regection filter selection
 
-#define MAX31856_REG_CR1    0x01
+#define MAX31856_REG_CR1    ((uint8_t)0x01)
-#define MAX31856_REG_CR1_AVGSEL_1   0x00
+#define MAX31856_REG_CR1_AVGSEL_1   ((uint8_t)0x70) // thermocouple voltage convertion 1 semple averaging
-#define MAX31856_REG_CR1_AVGSEL_2   0x10
+#define MAX31856_REG_CR1_AVGSEL_2   ((uint8_t)0x10) // thermocouple voltage convertion 2 semples averaging
-#define MAX31856_REG_CR1_AVGSEL_4   0x20
+#define MAX31856_REG_CR1_AVGSEL_4   ((uint8_t)0x20) // thermocouple voltage convertion 4 semples averaging
-#define MAX31856_REG_CR1_AVGSEL_8   0x30
+#define MAX31856_REG_CR1_AVGSEL_8   ((uint8_t)0x30) // thermocouple voltage convertion 8 semples averaging
-#define MAX31856_REG_CR1_AVGSEL_16  0x40
+#define MAX31856_REG_CR1_AVGSEL_16  ((uint8_t)0x40) // thermocouple voltage convertion 16 semples averaging
-#define MAX31856_REG_CR1_TC_TYPE_B  0x00
+#define MAX31856_REG_CR1_TC_TYPE_B  ((uint8_t)0x00) // thermocouple type B
-#define MAX31856_REG_CR1_TC_TYPE_E  0x01
+#define MAX31856_REG_CR1_TC_TYPE_E  ((uint8_t)0x01) // thermocouple type E
-#define MAX31856_REG_CR1_TC_TYPE_J  0x02
+#define MAX31856_REG_CR1_TC_TYPE_J  ((uint8_t)0x02) // thermocouple type J
-#define MAX31856_REG_CR1_TC_TYPE_K  0x03
+#define MAX31856_REG_CR1_TC_TYPE_K  ((uint8_t)0x03) // thermocouple type K
-#define MAX31856_REG_CR1_TC_TYPE_N  0x04
+#define MAX31856_REG_CR1_TC_TYPE_N  ((uint8_t)0x04) // thermocouple type N
-#define MAX31856_REG_CR1_TC_TYPE_R  0x05
+#define MAX31856_REG_CR1_TC_TYPE_R  ((uint8_t)0x05) // thermocouple type R
-#define MAX31856_REG_CR1_TC_TYPE_S  0x06
+#define MAX31856_REG_CR1_TC_TYPE_S  ((uint8_t)0x06) // thermocouple type S
-#define MAX31856_REG_CR1_TC_TYPE_T  0x07
+#define MAX31856_REG_CR1_TC_TYPE_T  ((uint8_t)0x07) // thermocouple type T
-#define MAX31856_REG_CR1_VM_GAIN8   0x08
+#define MAX31856_REG_CR1_VM_GAIN8   ((uint8_t)0x08) // voltage mode, gain 8
-#define MAX31856_REG_CR1_VM_GAIN32  0x0C
+#define MAX31856_REG_CR1_VM_GAIN32  ((uint8_t)0x0C) // voltage mode, gain 32
 
-#define MAX31856_REG_MASK   0x02
+#define MAX31856_REG_MASK   ((uint8_t)0x02) // fault mask
-#define MAX31856_REG_CJHF   0x03
+#define MAX31856_REG_CJHF   ((uint8_t)0x03) // cold juntion hige fault theshold
-#define MAX31856_REG_CJLF   0x04
+#define MAX31856_REG_CJLF   ((uint8_t)0x04) // cold juntion low fault theshold
-#define MAX31856_REG_LTHFTH 0x05
+#define MAX31856_REG_LTHFTH ((uint8_t)0x05) 
-#define MAX31856_REG_LTHFTL 0x06
+#define MAX31856_REG_LTHFTL ((uint8_t)0x06)
-#define MAX31856_REG_LTLFTH 0x07
+#define MAX31856_REG_LTLFTH ((uint8_t)0x07)
-#define MAX31856_REG_LTLFTL 0x08
+#define MAX31856_REG_LTLFTL ((uint8_t)0x08)
-#define MAX31856_REG_CJTO   0x09
+#define MAX31856_REG_CJTO   ((uint8_t)0x09) // cold juntion temp offset
-#define MAX31856_REG_CJTH   0x0A
+#define MAX31856_REG_CJTH   ((uint8_t)0x0A) // cold juntion temp hige byte
-#define MAX31856_REG_CJTL   0x0B
+#define MAX31856_REG_CJTL   ((uint8_t)0x0B) // cold juntion temp low byte
+#define MAX31856_REG_LTCBH  ((uint8_t)0x0C) // thermocouple temp byte 2
+#define MAX31856_REG_LTCBM  ((uint8_t)0x0D) // thermocouple temp byte 1
+#define MAX31856_REG_LTCBL  ((uint8_t)0x0E) // thermocouple temp byte 0
+#define MAX31856_REG_SR     ((uint8_t)0x0F) // fault status
+
+// max31856 pins
+#define SPI_MAX31856            spi0
+#define SPI_MAX31856_BOUD       1000E3 // 1 MHz (max31856 can go up to 5 MHz)
+#define SPI_MAX31856_SPO        SPI_CPOL_0
+#define SPI_MAX31856_SPH        SPI_CPHA_1
+#define SPI_MAX31856_BIT_ORDER  SPI_MSB_FIRST
+#define SPI_MAX31856_BLOCK_SIZE 8
 
 #endif