AN434

Rev. 0.4

9

4. Device Configuration Reports

4.1. Set Reset Device

Report ID: 0x40

Direction: Control Out

Set Reset Device is used to restart the device from the USB host. The device will re-enumerate on the USB bus

and all UART configuration settings are reset to their default values.

For certain operating systems such as Windows, initiating a device reset and re-enumerating will make the device's

handle stale. The user application is responsible for handling this "surprise disconnect" event. See AN433: CP2110

HID-to-UART API Specification for more information regarding surprise disconnects.

4.2. Get/Set UART Enable

Report ID: 0x41

Direction: Control In/Out

Get UART Enable returns the Enable status of the UART. The UART is disabled by default.

Set UART Enable checks the FlushBuffers programmed parameter and purges the FIFOs depending on the

parameter Enable or Disable, which are treated as Open and Close respectively.

4.3. Get UART Status

Report ID: 0x42

Direction: Control In

TX FIFO is the number of bytes left for the device transfer to the UART-based device. The transmit FIFO buffer can

hold up to 480 bytes. The value returned is a two-byte, unsigned integer.

RX FIFO is the number of bytes left for the device to transfer to the USB host. The receive FIFO buffer can hold up

to 480 bytes. The value returned is a two-byte, unsigned integer.

Error Status indicates if a Parity error (mask 0x01) or Overrun error (0x02) has occurred since the last time Error

Status was read by the user. Reading Error Status clears the errors.

Break Status indicates if a line break is currently in progress.

Name

Offset

Size

Value

Description

Reset Type

1

1

0x00

Reset with re-enumeration

Name

Offset

Size

Value

Description

UART Enable

1

1

0x00

0x01

UART disabled

UART enabled

Name

Offset

Size

Value

Description

TX FIFO

1

2

See below

Number of bytes in Transmit FIFO

RX FIFO

3

2

See below

Number of bytes in the Receive FIFO

Error Status

5

1

See below

Parity and Overrun errors

Break Status

6

1

0x00

0x01

Line break is not active

Line break is active