add schematic

README.md

@@ -15,7 +15,8 @@ You will need the following hardware to make the device:
 - Raspberry Pi Pico W
 - USB extension cable
 
-![Wiring of USB connectors to Raspberry Pi Pico W](diagram.png)
+![Wiring schematic](schematic.svg)
+
 
 You will need to cut the USB extension in half and connect the wires from the
 female end to the Raspberry Pi Pico W. The default configuration is to attach
@@ -32,6 +33,8 @@ respectively. For the data wires, you can solder them to the two test points
 TP2 and TP3 on the back of the Raspberry Pi Pico. The white cable goes to TP2
 and the green cable to TP3.
 
+![Wiring of USB connectors to Raspberry Pi Pico W](diagram.png)
+
 The individual wires on the USB can be fragile, so hot glue or other strain
 relief is a good idea. 
 

bt_device.c

@@ -51,8 +51,6 @@ void btstack_main(void){
 	bt_hid_setup();
 
 	init_report_buf();
-
-	hci_power_control(HCI_POWER_ON);
 }
 
 static void bt_hid_setup(void) {

main.c

@@ -16,9 +16,12 @@ static void usb_main(void);
 
 // main loop
 int main(void) {
-
+	// for PIO USB, we want clock speed to be multiple of 12MHz
 	set_sys_clock_khz(144000, true);
 
+	// need so BTstack can save pairing information to flash
+	flash_safe_execute_core_init();
+
 	sleep_ms(10);
 
 	// run BLE on core 1

usb_host.c

@@ -18,7 +18,7 @@
 host_state_t host_state;
 static absolute_time_t request_time;
 static absolute_time_t last_report;
-static uint16_t host_poll_interval=8000;
+static uint16_t host_poll_interval=HOST_POLL_INTERVAL;
 
 // initialize usb host
 void usb_host_init(void) {

usb_host.h

@@ -1,7 +1,7 @@
 #ifndef USB_HOST_H_
 #define USB_HOST_H_
 
-#define HOST_POLL_INTERVAL	25000
+#define HOST_POLL_INTERVAL	8000
 
 typedef enum {
 	HOST_INACTIVE=0,