Update ATtiny84 firmware to use Volume Up for shutdown, configure KeyMapper, and document automatic boot hotspot

Arduino/LIN_to_IR/LIN_to_IR.cpp

@@ -85,7 +85,7 @@ uint32_t get_mce_code(uint8_t button) {
     case 4: return 0x800f0421; // RIGHT
     case 5: return 0x800f0422; // ENTER / OK
     case 6: return 0x800f0423; // BACK
-    case 7: return 0x800f046f; // F12 (Shutdown)
+    case 7: return 0x800f0410; // Volume Up (Shutdown)
     default: return 0;
   }
 }
@@ -210,7 +210,7 @@ void loop() {
     current_button = 0;
   }
 
-  // Car off detection: if no LIN activity for 5 seconds, send F12 to trigger shutdown
+  // Car off detection: if no LIN activity for 5 seconds, send Volume Up to trigger shutdown
   if (is_car_on && (millis() - last_lin_activity_time > 5000)) {
     is_car_on = false;
     for (int i = 0; i < 3; i++) {

Arduino/LIN_to_IR/README.md

@@ -27,7 +27,7 @@ The Steering Wheel Module (SWM) sends frames on LIN ID `0x20` with the navigatio
 | **RIGHT** | `d0 & 0x08` | `4` | `0x800f0421` | Navigate Right |
 | **ENTER** | `d1 & 0x08` | `5` | `0x800f0422` | Select / OK |
 | **BACK** | `d1 & 0x01` | `6` | `0x800f0423` | Back / Exit |
-| **F12 (Shutdown)** | LIN Silent > 5s | `7` | `0x800f046f` | Trigger Shutdown (via MacroDroid) |
+| **Volume Up (Shutdown)** | LIN Silent > 5s | `7` | `0x800f0410` | Trigger Shutdown (via KeyMapper) |
 
 *Note: In previous revisions, `ENTER` and `BACK` were reversed. This has been corrected so that pressing `ENTER` maps to `0x800f0422` and `BACK` maps to `0x800f0423`.*
 
@@ -36,35 +36,65 @@ The Steering Wheel Module (SWM) sends frames on LIN ID `0x20` with the navigatio
 To automatically power off the Raspberry Pi when the car is turned off:
 1. **Activity Monitor**: The ATtiny monitors LIN bus activity. The Central Electronic Module (CEM) continuously polls the LIN bus when the ignition is on.
 2. **Timeout**: If no LIN serial data is received for 5 seconds, the ATtiny assumes the car is off.
-3. **Shutdown Signal**: It transitions the car status to "off" and sends the MCE code `0x800f046f` (mapped to `KEY_F12`) 3 times to ensure transmission reliability.
+3. **Shutdown Signal**: It transitions the car status to "off" and sends the MCE code `0x800f0410` (mapped to `KEY_VOLUMEUP`) 3 times to ensure transmission reliability.
 4. **State Protection**: It will not send the shutdown command again until the car is turned back on and LIN traffic resumes (which sets `is_car_on` back to `true`).
 
 ## Raspberry Pi Configuration
 
 ### 1. Keymap Setup
-Remap scancode `0x800f046f` to `KEY_F12` on the Raspberry Pi:
+Remap the MCE remote codes on the Raspberry Pi:
 - The custom TOML configuration is saved at `/data/rc-rc6-mce.toml` on the Pi.
 - To apply it dynamically:
   ```bash
   /vendor/bin/ir-keytable -w /data/rc-rc6-mce.toml
   ```
 
-### 2. MacroDroid Persistence & Trigger
-Configure two macros in **MacroDroid** to manage keymap loading and shutdown:
+### 2. KeyMapper Setup
+Instead of MacroDroid, **KeyMapper** is used to intercept the `KEY_VOLUMEUP` trigger from the direct-wired IR receiver and execute the shutdown command.
 
-- **Macro 1: Load Keymap on Boot**
-  - **Trigger**: *Device Boot*
-  - **Action**: *Run Shell Command* (Check **Run as Root**)
-    ```bash
-    /vendor/bin/ir-keytable -w /data/rc-rc6-mce.toml
-    ```
+To configure KeyMapper completely via command-line:
+- **Enable Accessibility Service**:
+  ```bash
+  adb shell settings put secure accessibility_enabled 1
+  adb shell settings put secure enabled_accessibility_services io.github.sds100.keymapper/.system.accessibility.MyAccessibilityService
+  ```
+- **Grant Do Not Disturb Access** (to prevent warnings on volume key mapping):
+  ```bash
+  adb shell settings put secure enabled_notification_policy_access_packages io.github.sds100.keymapper
+  ```
+- **Map Trigger and Action**:
+  The preconfigured KeyMapper SQLite database is pushed directly to the device. The Volume Up key is mapped to run the command:
+  ```bash
+  reboot -p
+  ```
 
-- **Macro 2: Shutdown on F12**
-  - **Trigger**: *Media / Key Pressed* -> Select **F12**
-  - **Action**: *Run Shell Command* (Check **Run as Root**)
-    ```bash
-    reboot -p
-    ```
+### 3. Wi-Fi Hotspot Auto-start Setup
+To enable the Wi-Fi hotspot (`VolvoC70_AndroidAuto` with passphrase `123456789`) automatically at startup:
+- A boot shell script `/system/bin/start_hotspot.sh` is defined to wait for boot completion and start the SoftAP.
+- A custom Android init service configuration `/system/etc/init/start_hotspot.rc` starts it when `sys.boot_completed` transitions to `1`.
+
+**Script (`/system/bin/start_hotspot.sh`):**
+```sh
+#!/system/bin/sh
+while [ "$(getprop sys.boot_completed)" != "1" ]; do
+    sleep 1
+done
+sleep 5
+cmd wifi start-softap VolvoC70_AndroidAuto wpa2 123456789
+```
+
+**Init Service (`/system/etc/init/start_hotspot.rc`):**
+```rc
+service start_hotspot /system/bin/sh /system/bin/start_hotspot.sh
+    class main
+    user root
+    group root system wifi
+    oneshot
+    disabled
+
+on property:sys.boot_completed=1
+    start start_hotspot
+```
 
 ## Protocol and Timing
 

Kicad/PCB_AndroidAuto.kicad_pro

@@ -514,7 +514,6 @@
         "priority": 2147483647,
         "schematic_color": "rgba(0, 0, 0, 0.000)",
         "track_width": 0.2,
-        "tuning_profile": "",
         "via_diameter": 0.6,
         "via_drill": 0.3,
         "wire_width": 6
@@ -533,7 +532,6 @@
         "priority": 0,
         "schematic_color": "rgba(0, 0, 0, 0.000)",
         "track_width": 1.37,
-        "tuning_profile": "",
         "via_diameter": 0.6,
         "via_drill": 0.3,
         "wire_width": 6
@@ -552,7 +550,6 @@
         "priority": 1,
         "schematic_color": "rgba(0, 0, 0, 0.000)",
         "track_width": 0.5,
-        "tuning_profile": "",
         "via_diameter": 0.8,
         "via_drill": 0.4,
         "wire_width": 6
@@ -571,14 +568,13 @@
         "priority": 2,
         "schematic_color": "rgba(0, 0, 0, 0.000)",
         "track_width": 0.15,
-        "tuning_profile": "",
         "via_diameter": 0.5,
         "via_drill": 0.4,
         "wire_width": 6
       }
     ],
     "meta": {
-      "version": 5
+      "version": 4
     },
     "net_colors": null,
     "netclass_assignments": null,
@@ -599,8 +595,10 @@
       "idf": "",
       "netlist": "",
       "plot": "",
+      "pos_files": "",
       "specctra_dsn": "",
       "step": "3D/PCB_AndroidAuto.stp",
+      "svg": "",
       "vrml": ""
     },
     "page_layout_descr_file": ""
@@ -724,8 +722,14 @@
     "page_layout_descr_file": "",
     "plot_directory": "",
     "reuse_designators": true,
+    "space_save_all_events": true,
     "spice_adjust_passive_values": false,
+    "spice_current_sheet_as_root": false,
     "spice_external_command": "spice \"%I\"",
+    "spice_model_current_sheet_as_root": true,
+    "spice_save_all_currents": false,
+    "spice_save_all_dissipations": false,
+    "spice_save_all_voltages": false,
     "subpart_first_id": 65,
     "subpart_id_separator": 0,
     "top_level_sheets": [