Maintainer	Bas van Dijk <v.dijk.bas@gmail.com>

System.USB.IO.Synchronous

Contents

Control transfers
Bulk transfers
Interrupt transfers

Description

This module provides functionality for performing control, bulk and interrupt transfers.

Synopsis

Documentation

type ReadAction = Size -> Timeout -> IO (ByteString, TimedOut)Source

Handy type synonym for read transfers.

A ReadAction is a function which takes a Size which defines how many bytes to read and a Timeout. The function returns an IO action which, when executed, performs the actual read and returns the ByteString that was read paired with a flag which indicates whether a transfer timed out.

type WriteAction = ByteString -> Timeout -> IO (Size, TimedOut)Source

Handy type synonym for write transfers.

A WriteAction is a function which takes a ByteString to write and a Timeout. The function returns an IO action which, when exectued, returns the number of bytes that were actually written paired with an flag which indicates whether a transfer timed out.

type Timeout = Int Source

A timeout in milliseconds. A timeout defines how long a transfer should wait before giving up due to no response being received. For no timeout, use value 0.

type TimedOut = Bool Source

True when a transfer timed out and False otherwise.

type Size = Int Source

Number of bytes transferred.

Control transfers

type ControlAction α = RequestType -> Recipient -> Request -> Value -> Index -> αSource

Handy type synonym that names the parameters of a control transfer.

data RequestType Source

Constructors

Standard
Class
Vendor

Instances

Enum RequestType
Eq RequestType
Data RequestType
Read RequestType
Show RequestType
Typeable RequestType

data Recipient Source

Constructors

ToDevice
ToInterface
ToEndpoint
ToOther

Instances

Enum Recipient
Eq Recipient
Data Recipient
Read Recipient
Show Recipient
Typeable Recipient

type Request = Word8 Source

type Value = Word16 Source

(Host-endian)

type Index = Word16 Source

(Host-endian)

control :: DeviceHandle -> ControlAction (Timeout -> IO ())Source

Perform a USB control request that does not transfer data.

Exceptions:

TimeoutException if the transfer timed out.
PipeException if the control request was not supported by the device
NoDeviceException if the device has been disconnected.
Another USBException.

readControl :: DeviceHandle -> ControlAction ReadAction Source

Perform a USB control read.

Exceptions:

PipeException if the control request was not supported by the device
NoDeviceException if the device has been disconnected.
Another USBException.

readControlExact :: DeviceHandle -> ControlAction (Size -> Timeout -> IO ByteString)Source

A convenience function similar to readControl which checks if the specified number of bytes to read were actually read. Throws an IOException if this is not the case.

writeControl :: DeviceHandle -> ControlAction WriteAction Source

Perform a USB control write.

Exceptions:

PipeException if the control request was not supported by the device
NoDeviceException if the device has been disconnected.
Another USBException.

Bulk transfers

readBulk Source

Arguments

:: DeviceHandle	A handle for the device to communicate with.
-> EndpointAddress	The address of a valid `In` and `Bulk` endpoint to communicate with. Make sure the endpoint belongs to the current alternate setting of a claimed interface which belongs to the device.
-> ReadAction

Perform a USB bulk read.

Exceptions:

PipeException if the endpoint halted.
OverflowException if the device offered more data, see Packets and overflows in the libusb documentation: http://libusb.sourceforge.net/api-1.0/packetoverflow.html.
NoDeviceException if the device has been disconnected.
Another USBException.

writeBulk Source

Arguments

:: DeviceHandle	A handle for the device to communicate with.
-> EndpointAddress	The address of a valid `Out` and `Bulk` endpoint to communicate with. Make sure the endpoint belongs to the current alternate setting of a claimed interface which belongs to the device.
-> WriteAction

Perform a USB bulk write.

Exceptions:

PipeException if the endpoint halted.
OverflowException if the device offered more data, see Packets and overflows in the libusb documentation: http://libusb.sourceforge.net/api-1.0/packetoverflow.html.
NoDeviceException if the device has been disconnected.
Another USBException.

Interrupt transfers

readInterrupt Source

Arguments

:: DeviceHandle	A handle for the device to communicate with.
-> EndpointAddress	The address of a valid `In` and `Interrupt` endpoint to communicate with. Make sure the endpoint belongs to the current alternate setting of a claimed interface which belongs to the device.
-> ReadAction

Perform a USB interrupt read.

Exceptions:

PipeException if the endpoint halted.
OverflowException if the device offered more data, see Packets and overflows in the libusb documentation: http://libusb.sourceforge.net/api-1.0/packetoverflow.html.
NoDeviceException if the device has been disconnected.
Another USBException.

writeInterrupt Source

Arguments

:: DeviceHandle	A handle for the device to communicate with.
-> EndpointAddress	The address of a valid `Out` and `Interrupt` endpoint to communicate with. Make sure the endpoint belongs to the current alternate setting of a claimed interface which belongs to the device.
-> WriteAction

Perform a USB interrupt write.

Exceptions:

PipeException if the endpoint halted.
OverflowException if the device offered more data, see Packets and overflows in the libusb documentation: http://libusb.sourceforge.net/api-1.0/packetoverflow.html.
NoDeviceException if the device has been disconnected.
Another USBException.