add ble scanning test

CMakeLists.txt

     src/debug.c
     src/buttons.c
     src/lipo.c
+    src/ble.c
 
     ${CMAKE_CURRENT_BINARY_DIR}/fatfs/ff.c
     ${CMAKE_CURRENT_BINARY_DIR}/fatfs/ffunicode.c

include/ble.h

+/*
+ * ble.h
+ *
+ * Copyright (c) 2023 Thomas Buck (thomas@xythobuz.de)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * See <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __BLE_H__
+#define __BLE_H__
+
+void ble_init(void);
+
+enum ble_scan_mode {
+    BLE_SCAN_OFF    = 0,
+    BLE_SCAN_ON     = 1,
+    BLE_SCAN_TOGGLE = 2,
+};
+void ble_scan(enum ble_scan_mode mode);
+
+#endif // __BLE_H__

include/lipo.h

 /*
  * lipo.h
  *
- * https://github.com/raspberrypi/pico-examples/blob/master/adc/read_vsys/power_status.c
- *
  * Copyright (c) 2023 Thomas Buck (thomas@xythobuz.de)
  *
  * This program is free software: you can redistribute it and/or modify

src/ble.c

+/*
+ * ble.c
+ *
+ * https://github.com/raspberrypi/pico-examples/blob/master/pico_w/bt/standalone/client.c
+ *
+ * Copyright (c) 2023 Thomas Buck (thomas@xythobuz.de)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * See <http://www.gnu.org/licenses/>.
+ */
+
+#include "btstack.h"
+#include "pico/cyw43_arch.h"
+
+#include "config.h"
+#include "log.h"
+#include "ble.h"
+
+enum ble_state {
+    TC_OFF = 0,
+    TC_IDLE,
+    TC_W4_SCAN_RESULT,
+    TC_W4_CONNECT,
+    TC_W4_SERVICE_RESULT,
+    TC_W4_CHARACTERISTIC_RESULT,
+    TC_W4_ENABLE_NOTIFICATIONS_COMPLETE,
+    TC_W4_READY
+};
+
+static btstack_packet_callback_registration_t hci_event_callback_registration;
+static enum ble_state state = TC_OFF;
+
+static bd_addr_t server_addr;
+static bd_addr_type_t server_addr_type;
+
+static void hci_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size) {
+    UNUSED(size);
+    UNUSED(channel);
+
+    if (packet_type != HCI_EVENT_PACKET) {
+        debug("unexpected packet 0x%02X", packet_type);
+        return;
+    }
+
+    switch (hci_event_packet_get_type(packet)) {
+    case BTSTACK_EVENT_STATE:
+            if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING) {
+                bd_addr_t local_addr;
+                gap_local_bd_addr(local_addr);
+                debug("BTstack up with %s", bd_addr_to_str(local_addr));
+                state = TC_IDLE;
+            } else {
+                debug("BTstack down (%d)", btstack_event_state_get_state(packet));
+                state = TC_OFF;
+            }
+        break;
+
+    case HCI_EVENT_COMMAND_COMPLETE:
+    case HCI_EVENT_TRANSPORT_PACKET_SENT:
+        break;
+
+    case GAP_EVENT_ADVERTISING_REPORT:
+        if (state != TC_W4_SCAN_RESULT) {
+            debug("scan result in invalid state %d", state);
+            return;
+        }
+
+        gap_event_advertising_report_get_address(packet, server_addr);
+        server_addr_type = gap_event_advertising_report_get_address_type(packet);
+        debug("Found device with addr %s", bd_addr_to_str(server_addr));
+        break;
+
+    case HCI_EVENT_LE_META:
+        switch (hci_event_le_meta_get_subevent_code(packet)) {
+            case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
+                break;
+
+            case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
+                debug("connection complete?!");
+                break;
+
+            default:
+                debug("unexpected LE meta event 0x%02X", hci_event_le_meta_get_subevent_code(packet));
+                break;
+        }
+        break;
+
+    default:
+        debug("unexpected event 0x%02X", hci_event_packet_get_type(packet));
+        break;
+    }
+}
+
+void ble_init(void) {
+    l2cap_init();
+    sm_init();
+    sm_set_io_capabilities(IO_CAPABILITY_NO_INPUT_NO_OUTPUT);
+
+    gatt_client_init();
+
+    hci_event_callback_registration.callback = &hci_event_handler;
+    hci_add_event_handler(&hci_event_callback_registration);
+
+    hci_power_control(HCI_POWER_ON);
+}
+
+void ble_scan(enum ble_scan_mode mode) {
+    switch (mode) {
+    case BLE_SCAN_OFF:
+        debug("stopping BLE scan");
+        state = TC_IDLE;
+        gap_stop_scan();
+        break;
+
+    case BLE_SCAN_ON:
+        debug("starting BLE scan");
+        state = TC_W4_SCAN_RESULT;
+        gap_set_scan_parameters(0,0x0030, 0x0030);
+        gap_start_scan();
+        break;
+
+    case BLE_SCAN_TOGGLE:
+        switch (state) {
+        case TC_W4_SCAN_RESULT:
+            ble_scan(0);
+            break;
+
+        case TC_IDLE:
+            ble_scan(1);
+            break;
+
+        default:
+            debug("invalid state %d", state);
+            break;
+        }
+        break;
+
+    default:
+        debug("invalid mode %d", mode);
+        break;
+    }
+}

src/console.c

 #include "debug.h"
 #include "console.h"
 #include "lipo.h"
+#include "ble.h"
 
 #define CNSL_BUFF_SIZE 1024
 #define CNSL_REPEAT_MS 500
         println("   help - print this message");
         println("  mount - make mass storage medium (un)available");
         println("  power - show Lipo battery status");
+        println("   scan - start or stop BLE scan");
         println("Press Enter with no input to repeat last command.");
         println("Use repeat to continuously execute last command.");
         println("Stop this by calling repeat again.");
         println("Battery: %.2fV = %.1f%% @ %s",
                 volt, lipo_percentage(volt),
                 lipo_charging() ? "charging" : "draining");
+    } else if (strcmp(line, "scan") == 0) {
+        ble_scan(2);
     } else {
         println("unknown command \"%s\"", line);
     }

src/main.c

 #include "usb.h"
 #include "fat_disk.h"
 #include "buttons.h"
+#include "ble.h"
 
 int main(void) {
     heartbeat_init();
     // required for LiPo voltage reading
     adc_init();
 
+    // required for BLE and LiPo voltage reading
+    debug("cyw43_arch_init");
     if (cyw43_arch_init()) {
-        debug("cyw43_arch failed");
+        debug("cyw43_arch_init failed");
     }
 
+    debug("ble_init");
+    ble_init();
+
     debug("fat_disk_init");
     fat_disk_init();