serial
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serial

Send and receive from a serial port

Examples

When the button is clicked, this patch resets the modem, begins polling for a response, and stops polling when a response has been received

Discussion

The serial object works only with ports and devices supported by the standard serial driver. It does not work with USB ports and devices, unless a USB to Serial adaptor is connected.

Arguments

port [symbol]

Optional

Specifies the serial port to be used by the serial object. If alphabetic shortcuts (a-z) are used, a specifies the first logical serial port in the computer, and b - z are used to specify additional ports.

portname [symbol]

If actual portnames are used, the symbol is the name given by the Operating System to your port. The print to the serial object can be used to create a list of available portnames and alphabetic shortcuts. If the port chosen is currently in use or unavailable when the serial object is instantiated, an error message will be displayed and the object will not function. If no port is specified, the default port is a .

rate [int]

Optional

An optional argument may be used after the port name or alphabetic shortcut to specify the baud rate of the serial port (the default rate is 4800 baud). Any value is allowable (although not all ports can be set to all baud rates). Some common rates are 300, 600, 1200, 1800, 2400, 3600, 7200, 9600, 19200, 38400, 57600 and 115200.

data [int]

Optional

After the baud rate, the next arguments specifies the number of data bits for the serial port (the default is 8 data bits). Other possible values are 5, 6 and 7.

stop [int]

Optional

The next argument specifies the number of stop bits for the serial port. The default is 1. Other possible values are 1.5 (Windows only) and 2.

parity [int or symbol]

Optional

The next argument specifies the parity for the serial port (the default is no parity, specified by 0 or no ).Other possible values are odd , 1 (odd), even , and 2 (odd).

Attributes

autoopen [int]

Toggles automatically opening the serial port.

baud [int]

Sets the port's baud rate.

Possible values:

'300'
'1200'
'2400'
'4800'
'9600'
'14400'
'19200'
'28800'
'38400'
'57600'
'115200'

bufsize [int]

Sets the input buffer size used by the serial object.

chunk [int]

Sets the data chunk size (data list length) for output.

databits [int]

Sets the number of data bits (acceptable values are 5, 6, 7, or 8).

Possible values:

'5'
'6'
'7'
'8'

defer [int] (default: 1)

Defer Output

drain [int]

(Mac only) Toggles drain enable. When enabled, communication waits until all data has been transmitted to the terminal when writing. The default value is 0 (disabled).

dtr [int]

Enables or disables the DTR (data terminal ready) function of the serial port used by the serial object.

parity [int]

Sets the parity for the port. The options are:

0: no parity
1: odd
2: even

Possible values:

0 = 'no'
1 = 'odd'
2 = 'even'

poll [float] (default: 0.)

Poll Enable/Interval

serport [int]

Used by the object Inspector only. Users should use the port message.

Possible values:

0 = 'Bluetooth-Incoming-Port'
1 = 'Bluetooth-Modem'

stopbits [int]

Sets the number of stop bits used when communicating with the serial port.

Possible values:

'1'
'2'

xonxoff [int]

Enables Xon/Xoff serial flow control.

Common Box Attributes

annotation [symbol]

Sets the text that will be displayed in the Clue window when the user moves the mouse over the object.

background [int] (default: 0)

Adds or removes the object from the patcher's background layer. background 1 adds the object to the background layer, background 0 removes it. Objects in the background layer are shown behind all objects in the default foreground layer.

color [4 floats]

Sets the color for the object box outline.

fontface [int]

Sets the type style used by the object. The options are:

plain
bold
italic
bold italic

Possible values:

0 = 'regular'
1 = 'bold'
2 = 'italic'
3 = 'bold italic'

fontname [symbol]

Sets the object's font.

fontsize [float]

Sets the object's font size (in points).

Possible values:

'8'
'9'
'10'
'11'
'12'
'13'
'14'
'16'
'18'
'20'
'24'
'30'
'36'
'48'
'64'
'72'

hidden [int] (default: 0)

Toggles whether an object is hidden when the patcher is locked.

hint [symbol]

Sets the text that will be displayed in as a pop-up hint when the user moves the mouse over the object in a locked patcher.

ignoreclick [int] (default: 0)

Toggles whether an object ignores mouse clicks in a locked patcher.

patching_rect [4 floats] (default: 0. 0. 100. 0.)

Sets the position and size of the object in the patcher window.

position [2 floats]

g/s(set)

Sets the object's x and y position in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its size unchanged.

presentation [int] (default: 0)

Sets whether an object belongs to the patcher's presentation.

presentation_rect [4 floats] (default: 0. 0. 0. 0.)

Sets the x and y position and width and height of the object in the patcher's presentation, leaving its patching position unchanged.

rect [4 floats]

g/s(set)

Sets the x and y position and width and height of the object in both patching and presentation modes (if the object belongs to its patcher's presentation).

size [2 floats]

g/s(set)

Sets the object's width and height in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its position unchanged.

textcolor [float]

Sets the color for the object's text in RGBA format.

textjustification [int]

Text Justification

Possible values:

0 = 'left'
1 = 'center'
2 = 'right'

varname [symbol]

Sets the patcher's scripting name, which can be used to address the object by name in pattr, scripting messages to thispatcher, and the js object.

Messages

bang

Sends each character received on the serial port since the last bang message out the serial object's left outlet as an integer in the order that the characters were received. Before output data is sent, the message read , followed by a number specifying the number of bytes received is sent out the right outlet of the serial object.

int

Arguments

input [int]
Sends the number out the serial port accessed by the serial object. Numbers outside the range 0-255 are wrapped to that range using a modulo operator. After the data is sent, the message write , followed by a number specifying the number of bytes sent is sent out the right outlet of the serial object.

float

Arguments

input [float]
Converted to int .

list

Arguments

input [list]
Sends each number in the list out the serial port, in order. Numbers outside the range 0-255 are wrapped to that range using a modulo operator. After the data is sent, the message write , followed by a number specifying the number of bytes sent is sent out the right outlet of the serial object.

break

Sends a break command to the serial port used by the serial object. After the break has completed, the message break is sent out the object's right outlet.

close

Closes an open serial connection, permitting use of the serial port by other applications.

getport

Sends the name or shortcut of the currently open serial port out the serial object's right outlet, prepended by the word port .

port

Arguments

port [list]
The word port, followed by a symbol, specifies the serial port to be used by the object. If alphabetic shortcuts are used, a specifies the first logical serial port in the computer. b - z specify additional ports. If actual portnames are used, the symbol is the name given by the operating system to your port. See the print message for a way to list available portnames and alphabetic shortcuts. If the port chosen is currently in use or unavailable when the port message is sent, an error message will be displayed and the object will revert to its previously chosen port, or won't function if there was none.

print

Sends a list of available serial ports to the Max Console, along with their alphabetic shortcuts. The message port [portname] [portname] ... is also sent from the object's right outlet, with a list of available ports.

open

Opens a new serial connection.

refresh

Refreshes the list of known/available serial ports. See the print message for additional information.

reset

(Mac only) Resets the currently open serial port using the Basic Stamp initialization sequence.

Output

(serial output)

When a number or list is received in its inlet, serial sends the data out the specified serial port at the current baud rate.

int

When serial receives a bang message and characters have been received in the serial port, the received characters are sent as numbers in the order they were received.

list

When serial receives a bang message, characters have been received in the serial port, and chunking is enabled, the received characters are sent as a list in the order the characters were received. The length of the list is determined by the argument to the chunk message (see the message listing for chunk for more information).

Out right outlet: Reports error and status messages.

See Also

Name Description
match Watch for a message match, then output the message
spell Convert input to UTF-8 (Unicode) codes
vdp Control a videodisk player through a serial port
Max Comm Tutorial 2: Serial Communication Max Comm Tutorial 2: Serial Communication