Serial CHOP


The Serial CHOP is used for serial communication through an external port, using the RS-232 protocol. These ports are usually a 9 pin connector, or a USB port on new machines. (Using a USB port requires a USB-to-serial adaptor and driver.) All of a computer's available serial ports can be found in the Device Manager under the Windows operating system. Their names begin with 'COM'. Example: COM1, COM2, COM3, etc.

This CHOP monitors changes in its input channels, and sends the corresponding script through the serial connection. Any ASCII numeric digits '0'..'9' that are received, are stored and reflected in the output channel named 'return'.

When you need to receive more complex data, other than simple ASCII numbers use the Serial DAT.

See also Serial DAT, serialDAT_Class, Arduino.


Parameters - Port Page

Active active - This check box enables the serial connection.

State state - - The type of input transition to monitor.

  • Off to On offtoon -
  • While On on -
  • On to Off ontooff -
  • While Off off -
  • Value Change valuechange -

Port port - - Selects the COM port that the serial connection will use.

  • COM3 com3 -

Baud Rate baudrate - The maximum number of bits of information, including "control" bits, that are transmitted per second. Check your input device's default baud rate and set accordingly.

Baud Rate Menu baudmenu - - Use this menu to select from some commonly used baud rates.

  • 1200 1200 -
  • 2400 2400 -
  • 9600 9600 -
  • 19200 19200 -
  • 38400 38400 -
  • 57600 57600 -
  • 115200 115200 -
  • 230400 230400 -
  • 460800 460800 -
  • 921600 921600 -
  • 1382400 1382400 -

Data Bits databits - - This parameter sets the number of data bits sent in each. Data bits are transmitted "backwards". Backwards refers to the order of transmission, which is from least significant bit (LSB) to most significant bit (MSB). To interpret the data bits, you must read from right to left.

  • 6 6 -
  • 7 7 -
  • 8 8 -
  • 9 9 -

Parity parity - - This parameter can be set to none, even, or odd. The optional parity bit follows the data bits and is included as a simple means of error checking. Parity bits work by specifying ahead of time whether the parity of the transmission is to be even or odd. If the parity is set to be odd, the transmitter will then set the parity bit in such a way as to make an odd number of 1's among the data bits and the parity bit.

  • Even even -
  • Odd odd -
  • None none -

Stop Bits stopbits - - The last part of transmission packet consists of 1 or 2 Stop bits. The connection will now wait for the next Start bit.

  • 1 1 -
  • 2 2 -

Parameters - Scripts Page

Add more parameters as needed for additioanl scripts. These strings are sent out the serial port when the corresponding channel change is detected. For example, Script 2 is sent to the serial port when the third input channel goes from off to on. These scripts will also convert escape sequences like <CR> and \n for carriage returns and \r for line feed.

Script 0 script0 - Enter the script for Script 0 here.

Parameters - Common Page

Time Slice timeslice - Turning this on forces the channels to be "Time Sliced". A Time Slice is the time between the last cook frame and the current cook frame.

Scope scope - To determine which channels get affected, some CHOPs use a Scope string on the Common page. See Pattern Matching.

Sample Rate Match srselect - - Handle cases where multiple input CHOPs' sample rates are different. When Resampling occurs, the curves are interpolated according to the Interpolation Method Option, or "Linear" if the Interpolate Options are not available.

  • Resample At First Input's Rate first - Use rate of first input to resample others.
  • Resample At Maximum Rate max - Resample to the highest sample rate.
  • Resample At Minimum Rate min - Resample to the lowest sample rate.
  • Error If Rates Differ err - Doesn't accept conflicting sample rates.

Export Method exportmethod - - This will determine how to connect the CHOP channel to the parameter. Refer to the Export article for more information.

  • DAT Table by Index datindex - Uses the docked DAT table and references the channel via the index of the channel in the CHOP.
  • DAT Table by Name datname - Uses the docked DAT table and references the channel via the name of the channel in the CHOP.
  • Channel Name is Path:Parameter autoname - The channel is the full destination of where to export to, such has geo1/transform1:tx.

Export Root autoexportroot - This path points to the root node where all of the paths that exporting by Channel Name is Path:Parameter are relative to.

Export Table exporttable - The DAT used to hold the export information when using the DAT Table Export Methods (See above).

Operator Inputs

  • Input 0: -

Info CHOP Channels

Extra Information for the Serial CHOP can be accessed via an Info CHOP.

Common CHOP Info Channels

  • start - Start of the CHOP interval in samples.
  • length - Number of samples in the CHOP.
  • sample_rate - The samplerate of the channels in frames per second.
  • num_channels - Number of channels in the CHOP.
  • time_slice - 1 if CHOP is Time Slice enabled, 0 otherwise.
  • export_sernum - A count of how often the export connections have been updated.

Common Operator Info Channels

  • total_cooks - Number of times the operator has cooked since the process started.
  • cook_time - Duration of the last cook in milliseconds.
  • cook_frame - Frame number when this operator was last cooked relative to the component timeline.
  • cook_abs_frame - Frame number when this operator was last cooked relative to the absolute time.
  • cook_start_time - Time in milliseconds at which the operator started cooking in the frame it was cooked.
  • cook_end_time - Time in milliseconds at which the operator finished cooking in the frame it was cooked.
  • cooked_this_frame - 1 if operator was cooked this frame.
  • warnings - Number of warnings in this operator if any.
  • errors - Number of errors in this operator if any.

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