Added chaps for operators

0x001a_operators/.gitignore

@@ -1,5 +1,2 @@
-.idea
-_deps
-cmake-*
 build
-.DS_Store
+!.vscode/*

0x001a_operators/.vscode/.cortex-debug.peripherals.state.json

@@ -1 +0,0 @@
-[]

0x001a_operators/.vscode/.cortex-debug.registers.state.json

@@ -1 +0,0 @@
-[]

0x001a_operators/.vscode/c_cpp_properties.json

@@ -1,18 +1,22 @@
 {
-  "configurations": [
+    "configurations": [
-    {
+        {
-      "name": "Pico",
+            "name": "Pico",
-      "includePath": [
+            "includePath": [
-        "${workspaceFolder}/**",
+                "${workspaceFolder}/**",
-        "${env:PICO_SDK_PATH}/**"
+                "${userHome}/.pico-sdk/sdk/2.2.0/**"
-      ],
+            ],
-      "defines": [],
+            "forcedInclude": [
-      "compilerPath": "${env:PICO_INSTALL_PATH}/gcc-arm-none-eabi/bin/arm-none-eabi-gcc.exe",
+                "${workspaceFolder}/build/generated/pico_base/pico/config_autogen.h",
-      "cStandard": "c11",
+                "${userHome}/.pico-sdk/sdk/2.2.0/src/common/pico_base_headers/include/pico.h"
-      "cppStandard": "c++11",
+            ],
-      "intelliSenseMode": "linux-gcc-arm",
+            "defines": [],
-      "configurationProvider": "ms-vscode.cmake-tools"
+            "compilerPath": "${userHome}/.pico-sdk/toolchain/14_2_Rel1/bin/arm-none-eabi-gcc.exe",
-    }
+            "compileCommands": "${workspaceFolder}/build/compile_commands.json",
-  ],
+            "cStandard": "c17",
-  "version": 4
+            "cppStandard": "c++14",
+            "intelliSenseMode": "linux-gcc-arm"
+        }
+    ],
+    "version": 4
 }

0x001a_operators/.vscode/cmake-kits.json

@@ -0,0 +1,15 @@
+[
+    {
+        "name": "Pico",
+        "compilers": {
+            "C": "${command:raspberry-pi-pico.getCompilerPath}",
+            "CXX": "${command:raspberry-pi-pico.getCxxCompilerPath}"
+        },
+        "environmentVariables": {
+            "PATH": "${command:raspberry-pi-pico.getEnvPath};${env:PATH}"
+        },
+        "cmakeSettings": {
+            "Python3_EXECUTABLE": "${command:raspberry-pi-pico.getPythonPath}"
+        }
+    }
+]

0x001a_operators/.vscode/extensions.json

@@ -1,9 +1,9 @@
 {
-  "recommendations": [
+    "recommendations": [
-    "marus25.cortex-debug",
+        "marus25.cortex-debug",
-    "ms-vscode.cmake-tools",
+        "ms-vscode.cpptools",
-    "ms-vscode.cpptools",
+        "ms-vscode.cpptools-extension-pack",
-    "ms-vscode.cpptools-extension-pack",
+        "ms-vscode.vscode-serial-monitor",
-    "ms-vscode.vscode-serial-monitor"
+        "raspberry-pi.raspberry-pi-pico"
-  ]
+    ]
-}
+}

0x001a_operators/.vscode/launch.json

@@ -1,58 +1,50 @@
 {
-  "version": "0.2.0",
+    "version": "0.2.0",
-  "configurations": [
+    "configurations": [
-    {
+        {
-      "name": "Pico Debug (Cortex-Debug)",
+            "name": "Pico Debug (Cortex-Debug)",
-      "cwd": "${workspaceFolder}",
+            "cwd": "${userHome}/.pico-sdk/openocd/0.12.0+dev/scripts",
-      "executable": "${command:cmake.launchTargetPath}",
+            "executable": "${command:raspberry-pi-pico.launchTargetPath}",
-      "request": "launch",
+            "request": "launch",
-      "type": "cortex-debug",
+            "type": "cortex-debug",
-      "servertype": "openocd",
+            "servertype": "openocd",
-      "gdbPath": "arm-none-eabi-gdb",
+            "serverpath": "${userHome}/.pico-sdk/openocd/0.12.0+dev/openocd.exe",
-      "device": "RP2040",
+            "gdbPath": "${command:raspberry-pi-pico.getGDBPath}",
-      "configFiles": [
+            "device": "${command:raspberry-pi-pico.getChipUppercase}",
-        "interface/cmsis-dap.cfg",
+            "configFiles": [
-        "target/rp2040.cfg"
+                "interface/cmsis-dap.cfg",
-      ],
+                "target/${command:raspberry-pi-pico.getTarget}.cfg"
-      "svdFile": "${env:PICO_SDK_PATH}/src/rp2040/hardware_regs/rp2040.svd",
+            ],
-      "runToEntryPoint": "main",
+            "svdFile": "${userHome}/.pico-sdk/sdk/2.2.0/src/${command:raspberry-pi-pico.getChip}/hardware_regs/${command:raspberry-pi-pico.getChipUppercase}.svd",
-      "openOCDLaunchCommands": [
+            "runToEntryPoint": "main",
-        "adapter speed 1000"
+            // 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",
-      "name": "Pico Debug (Cortex-Debug with external OpenOCD)",
+                "load \"${command:raspberry-pi-pico.launchTargetPath}\""
-      "cwd": "${workspaceFolder}",
+            ],
-      "executable": "${command:cmake.launchTargetPath}",
+            "openOCDLaunchCommands": [
-      "request": "launch",
+                "adapter speed 5000"
-      "type": "cortex-debug",
+            ]
-      "servertype": "external",
+        },
-      "gdbTarget": "localhost:3333",
+        {
-      "gdbPath": "arm-none-eabi-gdb",
+            "name": "Pico Debug (Cortex-Debug with external OpenOCD)",
-      "device": "RP2040",
+            "cwd": "${workspaceRoot}",
-      "svdFile": "${env:PICO_SDK_PATH}/src/rp2040/hardware_regs/rp2040.svd",
+            "executable": "${command:raspberry-pi-pico.launchTargetPath}",
-      "runToEntryPoint": "main"
+            "request": "launch",
-    },
+            "type": "cortex-debug",
-    {
+            "servertype": "external",
-      "name": "Pico Debug (C++ Debugger)",
+            "gdbTarget": "localhost:3333",
-      "type": "cppdbg",
+            "gdbPath": "${command:raspberry-pi-pico.getGDBPath}",
-      "request": "launch",
+            "device": "${command:raspberry-pi-pico.getChipUppercase}",
-      "cwd": "${workspaceFolder}",
+            "svdFile": "${userHome}/.pico-sdk/sdk/2.2.0/src/${command:raspberry-pi-pico.getChip}/hardware_regs/${command:raspberry-pi-pico.getChipUppercase}.svd",
-      "program": "${command:cmake.launchTargetPath}",
+            "runToEntryPoint": "main",
-      "MIMode": "gdb",
+            // Fix for no_flash binaries, where monitor reset halt doesn't do what is expected
-      "miDebuggerPath": "arm-none-eabi-gdb",
+            // Also works fine for flash binaries
-      "miDebuggerServerAddress": "localhost:3333",
+            "overrideLaunchCommands": [
-      "debugServerPath": "openocd",
+                "monitor reset init",
-      "debugServerArgs": "-f interface/cmsis-dap.cfg -f target/rp2040.cfg -c \"adapter speed 1000\"",
+                "load \"${command:raspberry-pi-pico.launchTargetPath}\""
-      "serverStarted": "Listening on port .* for gdb connections",
+            ]
-      "filterStderr": true,
+        },
-      "stopAtEntry": true,
+    ]
-      "hardwareBreakpoints": {
-        "require": true,
-        "limit": 4
-      },
-      "preLaunchTask": "Flash",
-      "svdPath": "${env:PICO_SDK_PATH}/src/rp2040/hardware_regs/rp2040.svd"
-    }
-  ]
 }

0x001a_operators/.vscode/settings.json

@@ -1,30 +1,40 @@
 {
-    // These settings tweaks to the cmake plugin will ensure
+    "cmake.showSystemKits": false,
-    // that you debug using cortex-debug instead of trying to launch
+    "cmake.options.statusBarVisibility": "hidden",
-    // a Pico binary on the host
+    "cmake.options.advanced": {
-    "cmake.statusbar.advanced": {
+        "build": {
-        "debug": {
+            "statusBarVisibility": "hidden"
-            "visibility": "hidden"
         },
         "launch": {
-            "visibility": "hidden"
+            "statusBarVisibility": "hidden"
         },
-        "build": {
+        "debug": {
-            "visibility": "hidden"
+            "statusBarVisibility": "hidden"
-        },
-        "buildTarget": {
-            "visibility": "hidden"
         }
     },
-    "cmake.buildBeforeRun": true,
+    "cmake.configureOnEdit": false,
-    "cmake.configureOnOpen": true,
+    "cmake.automaticReconfigure": false,
-    "cmake.configureSettings": {
+    "cmake.configureOnOpen": false,
-      "CMAKE_MODULE_PATH": "${env:PICO_INSTALL_PATH}/pico-sdk-tools"
-    },
     "cmake.generator": "Ninja",
-    "C_Cpp.default.configurationProvider": "ms-vscode.cmake-tools",
+    "cmake.cmakePath": "${userHome}/.pico-sdk/cmake/v3.31.5/bin/cmake",
-    "C_Cpp.errorSquiggles": "enabled",
+    "C_Cpp.debugShortcut": false,
-    "files.associations": {
+    "terminal.integrated.env.windows": {
-        "stdlib.h": "c"
+        "PICO_SDK_PATH": "${env:USERPROFILE}/.pico-sdk/sdk/2.2.0",
-    }
+        "PICO_TOOLCHAIN_PATH": "${env:USERPROFILE}/.pico-sdk/toolchain/14_2_Rel1",
+        "Path": "${env:USERPROFILE}/.pico-sdk/toolchain/14_2_Rel1/bin;${env:USERPROFILE}/.pico-sdk/picotool/2.2.0-a4/picotool;${env:USERPROFILE}/.pico-sdk/cmake/v3.31.5/bin;${env:USERPROFILE}/.pico-sdk/ninja/v1.12.1;${env:PATH}"
+    },
+    "terminal.integrated.env.osx": {
+        "PICO_SDK_PATH": "${env:HOME}/.pico-sdk/sdk/2.2.0",
+        "PICO_TOOLCHAIN_PATH": "${env:HOME}/.pico-sdk/toolchain/14_2_Rel1",
+        "PATH": "${env:HOME}/.pico-sdk/toolchain/14_2_Rel1/bin:${env:HOME}/.pico-sdk/picotool/2.2.0-a4/picotool:${env:HOME}/.pico-sdk/cmake/v3.31.5/bin:${env:HOME}/.pico-sdk/ninja/v1.12.1:${env:PATH}"
+    },
+    "terminal.integrated.env.linux": {
+        "PICO_SDK_PATH": "${env:HOME}/.pico-sdk/sdk/2.2.0",
+        "PICO_TOOLCHAIN_PATH": "${env:HOME}/.pico-sdk/toolchain/14_2_Rel1",
+        "PATH": "${env:HOME}/.pico-sdk/toolchain/14_2_Rel1/bin:${env:HOME}/.pico-sdk/picotool/2.2.0-a4/picotool:${env:HOME}/.pico-sdk/cmake/v3.31.5/bin:${env:HOME}/.pico-sdk/ninja/v1.12.1:${env:PATH}"
+    },
+    "raspberry-pi-pico.cmakeAutoConfigure": true,
+    "raspberry-pi-pico.useCmakeTools": false,
+    "raspberry-pi-pico.cmakePath": "${HOME}/.pico-sdk/cmake/v3.31.5/bin/cmake",
+    "raspberry-pi-pico.ninjaPath": "${HOME}/.pico-sdk/ninja/v1.12.1/ninja"
 }

0x001a_operators/.vscode/tasks.json

@@ -1,29 +1,102 @@
 {
-  "version": "2.0.0",
+    "version": "2.0.0",
-  "tasks": [
+    "tasks": [
-    {
+        {
-      "label": "Flash",
+            "label": "Compile Project",
-      "type": "shell",
+            "type": "process",
-      "command": "openocd",
+            "isBuildCommand": true,
-      "args": [
+            "command": "${userHome}/.pico-sdk/ninja/v1.12.1/ninja",
-        "-f",
+            "args": ["-C", "${workspaceFolder}/build"],
-        "interface/cmsis-dap.cfg",
+            "group": "build",
-        "-f",
+            "presentation": {
-        "target/rp2040.cfg",
+                "reveal": "always",
-        "-c",
+                "panel": "dedicated"
-        "adapter speed 1000; program {${command:cmake.launchTargetPath}} verify reset exit"
+            },
-      ],
+            "problemMatcher": "$gcc",
-      "problemMatcher": []
+            "windows": {
-    },
+                "command": "${env:USERPROFILE}/.pico-sdk/ninja/v1.12.1/ninja.exe"
-    {
+            }
-      "label": "Build",
+        },
-      "type": "cmake",
+        {
-      "command": "build",
+            "label": "Run Project",
-      "problemMatcher": "$gcc",
+            "type": "process",
-      "group": {
+            "command": "${env:HOME}/.pico-sdk/picotool/2.2.0-a4/picotool/picotool",
-        "kind": "build",
+            "args": [
-        "isDefault": true
+                "load",
-      }
+                "${command:raspberry-pi-pico.launchTargetPath}",
-    }
+                "-fx"
-  ]
+            ],
+            "presentation": {
+                "reveal": "always",
+                "panel": "dedicated"
+            },
+            "problemMatcher": [],
+            "windows": {
+                "command": "${env:USERPROFILE}/.pico-sdk/picotool/2.2.0-a4/picotool/picotool.exe"
+            }
+        },
+        {
+            "label": "Flash",
+            "type": "process",
+            "command": "${userHome}/.pico-sdk/openocd/0.12.0+dev/openocd.exe",
+            "args": [
+                "-s",
+                "${userHome}/.pico-sdk/openocd/0.12.0+dev/scripts",
+                "-f",
+                "interface/cmsis-dap.cfg",
+                "-f",
+                "target/${command:raspberry-pi-pico.getTarget}.cfg",
+                "-c",
+                "adapter speed 5000; program \"${command:raspberry-pi-pico.launchTargetPath}\" verify reset exit"
+            ],
+            "problemMatcher": [],
+            "windows": {
+                "command": "${env:USERPROFILE}/.pico-sdk/openocd/0.12.0+dev/openocd.exe",
+            }
+        },
+        {
+            "label": "Rescue Reset",
+            "type": "process",
+            "command": "${userHome}/.pico-sdk/openocd/0.12.0+dev/openocd.exe",
+            "args": [
+                "-s",
+                "${userHome}/.pico-sdk/openocd/0.12.0+dev/scripts",
+                "-f",
+                "interface/cmsis-dap.cfg",
+                "-f",
+                "target/${command:raspberry-pi-pico.getChip}-rescue.cfg",
+                "-c",
+                "adapter speed 5000; reset halt; exit"
+            ],
+            "problemMatcher": [],
+            "windows": {
+                "command": "${env:USERPROFILE}/.pico-sdk/openocd/0.12.0+dev/openocd.exe",
+            }
+        },
+        {
+            "label": "RISC-V Reset (RP2350)",
+            "type": "process",
+            "command": "${userHome}/.pico-sdk/openocd/0.12.0+dev/openocd.exe",
+            "args": [
+                "-s",
+                "${userHome}/.pico-sdk/openocd/0.12.0+dev/scripts",
+                "-c",
+                "set USE_CORE { rv0 rv1 cm0 cm1 }",
+                "-f",
+                "interface/cmsis-dap.cfg",
+                "-f",
+                "target/rp2350.cfg",
+                "-c",
+                "adapter speed 5000; init;",
+                "-c",
+                "write_memory 0x40120158 8 { 0x3 }; echo [format \"Info : ARCHSEL 0x%02x\" [read_memory 0x40120158 8 1]];",
+                "-c",
+                "reset halt; targets rp2350.rv0; echo [format \"Info : ARCHSEL_STATUS 0x%02x\" [read_memory 0x4012015C 8 1]]; exit"
+            ],
+            "problemMatcher": [],
+            "windows": {
+                "command": "${env:USERPROFILE}/.pico-sdk/openocd/0.12.0+dev/openocd.exe",
+            }
+        }
+    ]
 }

0x001a_operators/0x001a_operators.c

@@ -1,9 +1,12 @@
 #include <stdio.h>
 #include "pico/stdlib.h"
+#include "dht11.h"
 
 int main(void) {
     stdio_init_all();
 
+    dht11_init(4);
+
     int x = 5;
     int y = 10;
     int arithmetic_operator = (x * y);
@@ -20,5 +23,14 @@ int main(void) {
         printf("logical_operator: %d\r\n", logical_operator);
         printf("bitwise_operator: %d\r\n", bitwise_operator);
         printf("assignment_operator: %d\r\n", assignment_operator);
+        
+        float hum, temp;
+        if (dht11_read(&hum, &temp)) {
+            printf("Humidity: %.1f%%, Temperature: %.1f°C\r\n", hum, temp);
+        } else {
+            printf("DHT11 read failed\r\n");
+        }
+        
+        sleep_ms(2000);
     }
-}
+}

0x001a_operators/CMakeLists.txt

@@ -1,21 +1,57 @@
+# Generated Cmake Pico project file
+
 cmake_minimum_required(VERSION 3.13)
 
-include(pico_sdk_import.cmake)
-project(0x001a_operators C CXX ASM)
 set(CMAKE_C_STANDARD 11)
 set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
+# Initialise pico_sdk from installed location
+# (note this can come from environment, CMake cache etc)
+
+# == DO NOT EDIT THE FOLLOWING LINES for the Raspberry Pi Pico VS Code Extension to work ==
+if(WIN32)
+    set(USERHOME $ENV{USERPROFILE})
+else()
+    set(USERHOME $ENV{HOME})
+endif()
+set(sdkVersion 2.2.0)
+set(toolchainVersion 14_2_Rel1)
+set(picotoolVersion 2.2.0-a4)
+set(picoVscode ${USERHOME}/.pico-sdk/cmake/pico-vscode.cmake)
+if (EXISTS ${picoVscode})
+    include(${picoVscode})
+endif()
+# ====================================================================================
+set(PICO_BOARD pico2 CACHE STRING "Board type")
+
+# Pull in Raspberry Pi Pico SDK (must be before project)
+include(pico_sdk_import.cmake)
+
+project(0x001a_operators C CXX ASM)
+
+# Initialise the Raspberry Pi Pico SDK
 pico_sdk_init()
 
-add_executable(0x001a_operators
+# Add executable. Default name is the project name, version 0.1
-    main.c
-)
 
-pico_enable_stdio_usb(0x001a_operators 1)
+add_executable(0x001a_operators 0x001a_operators.c dht11.c )
+
+pico_set_program_name(0x001a_operators "0x001a_operators")
+pico_set_program_version(0x001a_operators "0.1")
+
+# Modify the below lines to enable/disable output over UART/USB
 pico_enable_stdio_uart(0x001a_operators 1)
+pico_enable_stdio_usb(0x001a_operators 0)
+
+# Add the standard library to the build
+target_link_libraries(0x001a_operators
+        pico_stdlib)
+
+# Add the standard include files to the build
+target_include_directories(0x001a_operators PRIVATE
+        ${CMAKE_CURRENT_LIST_DIR}
+)
 
 pico_add_extra_outputs(0x001a_operators)
 
-target_link_libraries(0x001a_operators 
-    pico_stdlib
-)

0x001a_operators/check_uf2.py

@@ -0,0 +1,83 @@
+"""
+Verify patched instruction and constant inside a UF2 file.
+
+Checks:
+- 0x10000410: should be 26 7a b4 ee (vsub.f32 s14, s14, s11)
+- 0x10000414: should be a6 7a b4 ee (vsub.f32 s15, s15, s11)
+- 0x1000042C: should be 00 00 00 41 (float 8.0)
+
+Usage:
+    python verify_uf2.py build/hacked.uf2
+"""
+
+import sys
+import struct
+
+UF2_MAGIC_START0 = 0x0A324655  # "UF2\n"
+UF2_MAGIC_START1 = 0x9E5D5157
+UF2_MAGIC_END    = 0x0AB16F30
+
+def load_uf2(path):
+    blocks = []
+    with open(path, "rb") as f:
+        data = f.read()
+    i = 0
+    while i + 512 <= len(data):
+        blk = data[i:i+512]
+        (m0, m1, flags, tgt_addr, payload_size, block_no,
+         num_blocks, file_size) = struct.unpack("<IIIIIIII", blk[:32])
+        if m0 != UF2_MAGIC_START0 or m1 != UF2_MAGIC_START1:
+            raise ValueError("Not a UF2 file or bad magic at block %d" % (i // 512))
+        if payload_size != 256:
+            raise ValueError("Unexpected payload size %d" % payload_size)
+        if struct.unpack("<I", blk[512-4:512])[0] != UF2_MAGIC_END:
+            raise ValueError("Bad end magic at block %d" % (i // 512))
+        payload = blk[32:32+payload_size]
+        blocks.append((tgt_addr, payload))
+        i += 512
+    return blocks
+
+def read_at(blocks, addr, length):
+    """Read 'length' bytes starting at virtual 'addr' from UF2 blocks."""
+    out = bytearray()
+    cur = addr
+    while len(out) < length:
+        # Find block that contains current address
+        hit = None
+        for base, pay in blocks:
+            if base <= cur < base + len(pay):
+                hit = (base, pay)
+                break
+        if not hit:
+            # If missing, fill with 0xFF (flash default) and continue
+            out.append(0xFF)
+            cur += 1
+            continue
+        base, pay = hit
+        out.append(pay[cur - base])
+        cur += 1
+    return bytes(out)
+
+def main():
+    if len(sys.argv) != 2:
+        print("Usage: python verify_uf2.py <path/to.uf2>")
+        sys.exit(1)
+    uf2_path = sys.argv[1]
+    blocks = load_uf2(uf2_path)
+
+    addrs = [0x10000410, 0x10000414, 0x1000042C]
+    labels = ["@10000410", "@10000414", "@1000042C"]
+
+    for label, a in zip(labels, addrs):
+        bytes_ = read_at(blocks, a, 4)
+        print(f"{label}: {bytes_.hex()} ", end="")
+        if a == 0x1000042C:
+            try:
+                print(f"(float {struct.unpack('<f', bytes_)[0]:.6f})")
+            except Exception:
+                print("(not a valid float)")
+        else:
+            print()
+
+if __name__ == "__main__":
+    main()

0x001a_operators/dht11.c

@@ -0,0 +1,79 @@
+/**
+ * @file dht11.c
+ * @brief Implementation of DHT11 temperature and humidity sensor driver
+ * @author Kevin Thomas
+ * @date 2025
+ * 
+ * MIT License
+ * 
+ * Copyright (c) 2025 Kevin Thomas
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "dht11.h"
+#include "hardware/gpio.h"
+#include "pico/time.h"
+
+static uint dht_pin;
+
+void dht11_init(uint8_t pin) {
+    dht_pin = pin;
+    gpio_init(pin);
+    gpio_pull_up(pin);
+}
+
+bool dht11_read(float *humidity, float *temperature) {
+    uint8_t data[5] = {0};
+    
+    // Start signal
+    gpio_set_dir(dht_pin, GPIO_OUT);
+    gpio_put(dht_pin, 0);
+    sleep_ms(18);
+    gpio_put(dht_pin, 1);
+    sleep_us(40);
+    gpio_set_dir(dht_pin, GPIO_IN);
+    
+    // Wait for response
+    uint32_t timeout = 10000;
+    while (gpio_get(dht_pin) == 1) if (--timeout == 0) return false;
+    timeout = 10000;
+    while (gpio_get(dht_pin) == 0) if (--timeout == 0) return false;
+    timeout = 10000;
+    while (gpio_get(dht_pin) == 1) if (--timeout == 0) return false;
+    
+    // Read 40 bits
+    for (int i = 0; i < 40; i++) {
+        timeout = 10000;
+        while (gpio_get(dht_pin) == 0) if (--timeout == 0) return false;
+        uint32_t start = time_us_32();
+        timeout = 10000;
+        while (gpio_get(dht_pin) == 1) if (--timeout == 0) return false;
+        uint32_t duration = time_us_32() - start;
+        data[i / 8] <<= 1;
+        if (duration > 40) data[i / 8] |= 1;
+    }
+    
+    // Check checksum
+    if (data[4] != ((data[0] + data[1] + data[2] + data[3]) & 0xFF)) return false;
+    
+    *humidity = data[0] + data[1] * 0.1f;
+    *temperature = data[2] + data[3] * 0.1f;
+    return true;
+}

0x001a_operators/dht11.h

@@ -0,0 +1,57 @@
+/**
+ * @file dht11.h
+ * @brief Header for DHT11 temperature and humidity sensor driver
+ * @author Kevin Thomas
+ * @date 2025
+ * 
+ * MIT License
+ * 
+ * Copyright (c) 2025 Kevin Thomas
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef DHT11_H
+#define DHT11_H
+
+#include <stdint.h>
+#include <stdbool.h>
+
+/**
+ * @brief Initialize the DHT11 driver
+ *
+ * Configures the GPIO pin for the DHT11 sensor. This must be called before
+ * using dht11_read().
+ *
+ * @param pin GPIO pin number connected to DHT11 signal
+ */
+void dht11_init(uint8_t pin);
+
+/**
+ * @brief Read temperature and humidity from DHT11 sensor
+ *
+ * Performs the DHT11 communication protocol to read sensor data.
+ *
+ * @param humidity Pointer to store humidity value (0-100%)
+ * @param temperature Pointer to store temperature value in Celsius
+ * @return true if read successful, false on error or timeout
+ */
+bool dht11_read(float *humidity, float *temperature);
+
+#endif // DHT11_H

0x001a_operators/hack-temp.py

@@ -0,0 +1,219 @@
+#!/usr/bin/env python3
+
+"""
+FILE: safe_patch.py
+
+DESCRIPTION:
+Incremental firmware patcher with minimal, conservative steps to bias readings.
+
+BRIEF:
+Provides three modes:
+- pool_only: change only the literal pool constant (scaling effect; least invasive)
+- temp_only_vadd: convert temperature path to vadd.f32 and set a small negative pool
+- both_vadd: convert both paths to vadd.f32 and set a small negative pool
+
+Intended to let you test changes incrementally, keeping humidity stable while
+you evaluate temperature bias first.
+
+AUTHOR: Kevin Thomas
+CREATION DATE: November 1, 2025
+UPDATE DATE: November 1, 2025
+"""
+
+import sys
+import os
+import struct
+
+BIN_PATH = "build/0x001a_operators.bin"
+
+# Offsets
+OFF_410 = 0x410
+OFF_414 = 0x414
+OFF_POOL = 0x42C
+
+# Original encodings (for visibility only)
+ORIG_410 = bytes.fromhex("a6ee257a")  # vfma.f32 s14, s12, s11
+ORIG_414 = bytes.fromhex("e6eea57a")  # vfma.f32 s15, s13, s11
+ORIG_POOL = bytes.fromhex("cccccc3d")  # 0.1f
+
+# Encodings for vadd.f32 s14, s14, s11 and vadd.f32 s15, s15, s11
+VADD_S14_S11 = struct.pack("<I", 0xEEB47A06)  # 06 7a b4 ee
+VADD_S15_S11 = struct.pack("<I", 0xEEB47A86)  # 86 7a b4 ee
+
+
+def read_at(path, offset, n):
+    """Read bytes from a binary file at a given offset.
+
+    Parameters
+    ----------
+    path : str
+        Filesystem path to the binary file.
+    offset : int
+        Byte offset from the start of the file.
+    n : int
+        Number of bytes to read.
+
+    Returns
+    -------
+    bytes
+        The raw bytes read from the file.
+
+    Raises
+    ------
+    IOError
+        If the file cannot be opened or read.
+    """
+    with open(path, "rb") as f:
+        f.seek(offset)
+        return f.read(n)
+
+
+def write_at(path, offset, data):
+    """Write bytes into a binary file at a given offset.
+
+    Parameters
+    ----------
+    path : str
+        Filesystem path to the binary file.
+    offset : int
+        Byte offset from the start of the file.
+    data : bytes
+        Bytes to write into the file.
+
+    Raises
+    ------
+    IOError
+        If the file cannot be opened or written.
+    """
+    with open(path, "rb+") as f:
+        f.seek(offset)
+        f.write(data)
+
+
+def fmt_float(b):
+    """Format a 4-byte sequence as hex and float if possible.
+
+    Parameters
+    ----------
+    b : bytes
+        A 4-byte sequence.
+
+    Returns
+    -------
+    str
+        Hexadecimal string with float interpretation if valid.
+    """
+    hx = b.hex()
+    try:
+        val = struct.unpack("<f", b)[0]
+        return f"{hx} (float {val:.6f})"
+    except Exception:
+        return hx
+
+
+def patch_pool_only(new_pool_float=-1.0):
+    """Patch only the pool constant to a new float value.
+
+    Parameters
+    ----------
+    new_pool_float : float, optional
+        New float value to write into the pool constant (default -1.0).
+
+    Returns
+    -------
+    None
+    """
+    print("[mode] pool_only")
+    curp = read_at(BIN_PATH, OFF_POOL, 4)
+    print(f"Current @0x1000042C: {fmt_float(curp)} (expected {ORIG_POOL.hex()} == 0.1f)")
+    newb = struct.pack("<f", new_pool_float)
+    write_at(BIN_PATH, OFF_POOL, newb)
+    chkp = read_at(BIN_PATH, OFF_POOL, 4)
+    print(f"Patched @0x1000042C: {fmt_float(chkp)} (target {newb.hex()} == {new_pool_float}f)")
+
+
+def patch_temp_only_vadd(new_pool_float=-2.0):
+    """Patch temperature path to vadd and set pool to a small negative.
+
+    Parameters
+    ----------
+    new_pool_float : float, optional
+        New float value to write into the pool constant (default -2.0).
+
+    Returns
+    -------
+    None
+    """
+    print("[mode] temp_only_vadd")
+    cur414 = read_at(BIN_PATH, OFF_414, 4)
+    curp = read_at(BIN_PATH, OFF_POOL, 4)
+    print(f"Current @0x10000414: {cur414.hex()} (expected {ORIG_414.hex()})")
+    print(f"Current @0x1000042C: {fmt_float(curp)}")
+    write_at(BIN_PATH, OFF_414, VADD_S15_S11)
+    write_at(BIN_PATH, OFF_POOL, struct.pack("<f", new_pool_float))
+    chk414 = read_at(BIN_PATH, OFF_414, 4)
+    chkp = read_at(BIN_PATH, OFF_POOL, 4)
+    print(f"Patched @0x10000414: {chk414.hex()} (should be {VADD_S15_S11.hex()})")
+    print(f"Patched @0x1000042C: {fmt_float(chkp)} (target {new_pool_float}f)")
+
+
+def patch_both_vadd(new_pool_float=-2.0):
+    """Patch both humidity and temperature paths to vadd and set pool.
+
+    Parameters
+    ----------
+    new_pool_float : float, optional
+        New float value to write into the pool constant (default -2.0).
+
+    Returns
+    -------
+    None
+    """
+    print("[mode] both_vadd")
+    cur410 = read_at(BIN_PATH, OFF_410, 4)
+    cur414 = read_at(BIN_PATH, OFF_414, 4)
+    curp = read_at(BIN_PATH, OFF_POOL, 4)
+    print(f"Current @0x10000410: {cur410.hex()} (expected {ORIG_410.hex()})")
+    print(f"Current @0x10000414: {cur414.hex()} (expected {ORIG_414.hex()})")
+    print(f"Current @0x1000042C: {fmt_float(curp)}")
+    write_at(BIN_PATH, OFF_410, VADD_S14_S11)
+    write_at(BIN_PATH, OFF_414, VADD_S15_S11)
+    write_at(BIN_PATH, OFF_POOL, struct.pack("<f", new_pool_float))
+    chk410 = read_at(BIN_PATH, OFF_410, 4)
+    chk414 = read_at(BIN_PATH, OFF_414, 4)
+    chkp = read_at(BIN_PATH, OFF_POOL, 4)
+    print(f"Patched @0x10000410: {chk410.hex()} (should be {VADD_S14_S11.hex()})")
+    print(f"Patched @0x10000414: {chk414.hex()} (should be {VADD_S15_S11.hex()})")
+    print(f"Patched @0x1000042C: {fmt_float(chkp)} (target {new_pool_float}f)")
+
+
+def main():
+    """Dispatch patch mode and perform incremental modifications.
+
+    Returns
+    -------
+    None
+
+    Raises
+    ------
+    FileNotFoundError
+        If the binary file specified by BIN_PATH does not exist.
+    """
+    if not os.path.exists(BIN_PATH):
+        raise FileNotFoundError(f"Binary not found: {BIN_PATH}")
+    mode = (sys.argv[1] if len(sys.argv) > 1 else "pool_only").strip().lower()
+    if mode == "pool_only":
+        patch_pool_only(new_pool_float=-1.0)
+    elif mode == "temp_only_vadd":
+        patch_temp_only_vadd(new_pool_float=-2.0)
+    elif mode == "both_vadd":
+        patch_both_vadd(new_pool_float=-2.0)
+    else:
+        print(f"Unknown mode: {mode}")
+        print("Use: pool_only | temp_only_vadd | both_vadd")
+        sys.exit(2)
+
+
+if __name__ == "__main__":
+    main()
+    print("Patch complete. Convert to UF2 and flash. Test each mode incrementally.")

0x001a_operators/pico_sdk_import.cmake

@@ -3,6 +3,28 @@
 # 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}')")
@@ -18,9 +40,20 @@ if (DEFINED ENV{PICO_SDK_FETCH_FROM_GIT_PATH} AND (NOT PICO_SDK_FETCH_FROM_GIT_P
     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)
@@ -29,25 +62,40 @@ if (NOT PICO_SDK_PATH)
         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 ()
-        # GIT_SUBMODULES_RECURSE was added in 3.17
+        FetchContent_Declare(
-        if (${CMAKE_VERSION} VERSION_GREATER_EQUAL "3.17.0")
+                pico_sdk
-            FetchContent_Declare(
+                GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
-                    pico_sdk
+                GIT_TAG ${PICO_SDK_FETCH_FROM_GIT_TAG}
-                    GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
+        )
-                    GIT_TAG master
-                    GIT_SUBMODULES_RECURSE FALSE
-            )
-        else ()
-            FetchContent_Declare(
-                    pico_sdk
-                    GIT_REPOSITORY https://github.com/raspberrypi/pico-sdk
-                    GIT_TAG master
-            )
-        endif ()
 
         if (NOT pico_sdk)
             message("Downloading Raspberry Pi Pico SDK")
-            FetchContent_Populate(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})