Changes between Version 6 and Version 7 of uboot

Timestamp:

06/21/2024 07:24:29 PM (17 months ago)

Author:

Tim Harvey

Comment:

added USB ACM Gadget documentation (USB as a serial console)

uboot

@@ -715 +715 @@
 }}}
 
+This requires CONFIG_USB_FUNCTION_MASS_STORAGE to be enabled and a USB host controller that can operate in gadget mode
+
+
+[=#gadgetacm]
+==== USB CDC ACM (Serial) Gadget
+You can use USB in device mode for console input/output to a host PC which supports the standard CDC ACM USB driver:
+ * Examples:
+  - use only ACM for console
+{{{#!bash
+setenv stderr usbacm && setenv stdout usbacm && setenv stdin usbacm
+}}}
+  - use both ACM as well as original env based UART serial console (requires CONFIG_CONSOLE_MUX=y):
+{{{#!bash
+setenv stderr ${stderr},usbacm && setenv stdout ${stdout},usbacm && setenv stdin ${stdin},usbacm
+}}}
+
+After doing this on your host PC the device is connected to with a USB-C to Host cable you should see a USB ACM device enumerate and can use it:
+ * example on a Linux PC you will see the following in syslog (dmesg):
+{{{#!bash
+usb 3-10.5.5: new high-speed USB device number 21 using xhci_hcd
+usb 3-10.5.5: New USB device found, idVendor=0525, idProduct=a4a5, bcdDevice= 2.21
+usb 3-10.5.5: New USB device strings: Mfr=1, Product=2, SerialNumber=3
+usb 3-10.5.5: Product: USB download gadget
+usb 3-10.5.5: Manufacturer: Gateworks
+usb 3-10.5.5: SerialNumber: 445096
+usb-storage 3-10.5.5:1.0: USB Mass Storage device detected
+usb-storage 3-10.5.5:1.0: Quirks match for vid 0525 pid a4a5: 10000
+cdc_acm 3-10.5.5:1.0: ttyACM0: USB ACM device
+
+# connect to ttyACM0 with a terminal program such as screen/minicom/picocom
+screen /dev/ttyACM0
+}}}
+
+
+This requires CONFIG_USB_FUNCTION_ACM to be enabled and a USB host controller that can operate in gadget mode
+
 
 [=#pci]