CDC ACM

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USB CDC (Communications Device Class) ACM (Abstract Control Model) is a vendor-independent publicly documented protocol that can be used for emulating serial ports over USB.

CDC ACM is used to access the U-boot bootloader prompt over USB (see: U-boot#Using_usbtty_from_Linux).

Contents

Hardware specifics

Neo1973 and CDC ACM

The Neo1973 u-boot boot loader contains support for obtaining the boot loader prompt over USB CDC ACM.

The Openmoko kernel also contains CDC ACM device support, contained in the g_serial.ko kernel module.

Host PC and CDC ACM

Linux

Linux has a generic CDC ACM host-side implementation in the kernel module cdc_acm.ko

On 2.6.25 this is at "Device Drivers -> USB support (USB_SUPPORT [=y]) -> Support for Host-side USB (USB [=m]) -> USB Modem (CDC ACM) support (USB_ACM)"

Windows

FIXME

MacOS X

See the USB Serial section in the MacOS X article.


Specification

http://www.usb.org/developers/devclass_docs/usbcdc11.pdf (3.6.2.1)

See http://wiki.openmoko.org/wiki/USB_CDC_ACM from more information

Personal tools

USB CDC (Communications Device Class) ACM (Abstract Control Model) is a vendor-independent publicly documented protocol that can be used for emulating serial ports over USB.

CDC ACM is used to access the U-boot bootloader prompt over USB (see: U-boot#Using_usbtty_from_Linux).

Hardware specifics

Neo1973 and CDC ACM

The Neo1973 u-boot boot loader contains support for obtaining the boot loader prompt over USB CDC ACM.

The Openmoko kernel also contains CDC ACM device support, contained in the g_serial.ko kernel module.

Host PC and CDC ACM

Linux

Linux has a generic CDC ACM host-side implementation in the kernel module cdc_acm.ko

On 2.6.25 this is at "Device Drivers -> USB support (USB_SUPPORT [=y]) -> Support for Host-side USB (USB [=m]) -> USB Modem (CDC ACM) support (USB_ACM)"

Windows

FIXME

MacOS X

See the USB Serial section in the MacOS X article.


Specification

http://www.usb.org/developers/devclass_docs/usbcdc11.pdf (3.6.2.1)

See http://wiki.openmoko.org/wiki/USB_CDC_ACM from more information