System.Serial.Manager

Many serial devices allow multiple commands to run at once, and | return their results as they finish. To make use of this, | multiple commands needs to read and write to the serial port at | once, and the return values must somehow be sorted and returned | back to the callers.

Documentation

serialManager

Arguments

:: Handle

the handle to wrap

-> String

the termination string for commands received from the port

-> String

the termination string for command send to the port

-> IO SerialManager

serialManager takes produces a structure around a Handle to | handle multiple callers to the serial port. The return value is | the channel to which all commands will flow. Users should use | the wrapCommand function to access it instead of trying to | access its details directly.

closeSerialManager :: SerialManager -> IO ()

Having multiple serial managers running on the same port is a disaster waiting to happen. When you're done with a SerialManager, run closeSerialManager on it to shut it down.

wrapCommand

Arguments

:: String

The command to send

-> (String -> Bool)

The predicate to recognize the returning value

-> SerialManager

The serial port to access

-> IO String

The response from the port

All the commands to operate a SerialManager should be specializations of wrapCommand, created by applying it to the first three arguments, then using that thereafter as the command to the serial port.

For example, the Olympus IX-81 requires a login command from the user (2LOG IN) followed by rn as an end of line. The response will be 2LOG + followed by r. So a login command would look like

p = ("2LOG" `isPrefixOf`)

login mgr = wrapCommand "\r\n" "2LOG IN" p

wrapCommand uses functions of type 'String -> Bool' users can choose whether or not to match any given command based upon its contents, rather than just blindly saying whether it matches or not.

wrapCommandWithCallback

Arguments

:: String

The command to send

-> (String -> Bool)

The predicate to recognize the returning value

-> (String -> IO ())

The callback to run when the command returns

-> SerialManager

The serial port to access

-> IO ThreadId

The thread id in which the command is being run

Sometimes we don't want the current thread to block, but we still want some action when the a command returns from the serial port. To that end, wrapCommandWithCallback lets us pass a function of type 'String -> IO ()' to be executed when a response is recognized by the predicate.

data SerialManager

data SerialCommand

wrapDeafCommand

Arguments

:: String

The command to send

-> SerialManager

The serial port to access

-> IO ()

Some commands don't expect any response from the hardware on the far end. For these cases, use wrapDeafCommand.