add remote wakeup for HIDKeyboard

DeqingSun · DeqingSun · commit 7e2d7c2c0932 · 2026-01-26T01:08:04.000-05:00
diff --git a/ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBHIDKeyboard.c b/ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBHIDKeyboard.c
@@ -205,6 +205,8 @@ uint8_t USB_EP1_send() {
 }
 
 uint8_t Keyboard_press(__data uint8_t k) {
+  USB_RemoteWakeup(); // Wake up host if it's in suspend mode
+
   __data uint8_t i;
   if (k >= 136) { // it's a non-printing key (not a modifier)
     k = k - 136;
diff --git a/ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBconstant.c b/ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBconstant.c
@@ -38,7 +38,8 @@ __code USB_Descriptor_Configuration_t ConfigurationDescriptor = {
                .ConfigurationNumber = 1,
                .ConfigurationStrIndex = NO_DESCRIPTOR,
 
-               .ConfigAttributes = (USB_CONFIG_ATTR_RESERVED),
+               .ConfigAttributes =
+                   (USB_CONFIG_ATTR_RESERVED | USB_CONFIG_ATTR_REMOTEWAKEUP),
 
                .MaxPowerConsumption = USB_CONFIG_POWER_MA(200)},
 
diff --git a/ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBhandler.c b/ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBhandler.c
@@ -33,6 +33,10 @@ __xdata uint8_t keyboardProtocol = 1;
 
 __xdata uint8_t keyboardLedStatus = 0;
 
+// Track USB suspend state for remote wakeup
+volatile __bit usbSuspended = 0;
+
+void delayMicroseconds(__data uint16_t us);
 inline void NOP_Process(void) {}
 
 void USB_EP0_SETUP() {
@@ -472,15 +476,16 @@ void USBInterrupt(void) { // inline not really working in multiple files in SDCC
   if (UIF_SUSPEND) {
     UIF_SUSPEND = 0;
     if (USB_MIS_ST & bUMS_SUSPEND) { // Suspend
-
+      usbSuspended = 1;              // Mark USB as suspended
+      // Optionally put MCU to sleep here if needed
       // while ( XBUS_AUX & bUART0_TX );                    // Wait for Tx
       // SAFE_MOD = 0x55;
       // SAFE_MOD = 0xAA;
       // WAKE_CTRL = bWAK_BY_USB | bWAK_RXD0_LO;    // Wake up by USB or RxD0
       // PCON |= PD; // Chip sleep SAFE_MOD = 0x55; SAFE_MOD = 0xAA; WAKE_CTRL =
       // 0x00;
-
-    } else {             // Unexpected interrupt, not supposed to happen !
+    } else {             // Resume
+      usbSuspended = 0;  // USB is active again
       USB_INT_FG = 0xFF; // Clear interrupt flag
     }
   }
@@ -537,3 +542,18 @@ void USBDeviceEndPointCfg() {
       UEP_R_RES_ACK | UEP_T_RES_NAK; // Manual flip, OUT transaction returns
                                      // ACK, IN transaction returns NAK
 }
+
+// Trigger USB remote wakeup to wake host from suspend
+void USB_RemoteWakeup() {
+  if (usbSuspended && (ConfigurationDescriptor.Config.ConfigAttributes &
+                       USB_CONFIG_ATTR_REMOTEWAKEUP)) {
+    // Send resume signal: force DP/DM output resume/K state
+    // The Usb was running at full speed 12M mode
+
+    UDEV_CTRL |= bUD_LOW_SPEED;
+    delayMicroseconds(2000);
+    UDEV_CTRL &= ~bUD_LOW_SPEED;
+
+    usbSuspended = 0; // Mark as no longer suspended
+  }
+}
diff --git a/ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBhandler.h b/ch55xduino/ch55x/libraries/Generic_Examples/examples/05.USB/HidKeyboard/src/userUsbHidKeyboard/USBhandler.h
@@ -18,6 +18,9 @@ extern __data uint8_t SetupReq;
 volatile extern __xdata uint8_t UsbConfig;
 
 extern const __code uint8_t *__data pDescr;
+extern __xdata uint8_t keyboardProtocol;
+extern __xdata uint8_t keyboardLedStatus;
+extern volatile __bit usbSuspended;
 
 void USB_EP1_IN();
 void USB_EP1_OUT();
@@ -56,5 +59,6 @@ void USBInterrupt(void);
 void USBDeviceCfg();
 void USBDeviceIntCfg();
 void USBDeviceEndPointCfg();
+void USB_RemoteWakeup(); // Trigger remote wakeup
 
 #endif

Original file line number	Diff line number	Diff line change
`@@ -205,6 +205,8 @@ uint8_t USB_EP1_send() {`
`205`	`205`	`}`
`206`	`206`
`207`	`207`	`uint8_t Keyboard_press(__data uint8_t k) {`
	`208`	`+ USB_RemoteWakeup(); // Wake up host if it's in suspend mode`
	`209`	`+`
`208`	`210`	`__data uint8_t i;`
`209`	`211`	`if (k >= 136) { // it's a non-printing key (not a modifier)`
`210`	`212`	`k = k - 136;`