15 - 08 - 2018

Controllers library

Block FTDI

The block works with the next FTDI chips:

  • FT245BL, FT245BM: Every of 8 IO pins of the device can be set as digital input or digital output. The device works well in Asynchronous mode, so please set the parameter Mode of the block to Asynchronous.

FT245BL Data Sheet:

Compatible devices:

  • FT245RL: The chip has 8 IO pins, which can be set as digital input ot output, but works well with Synchronous mode, in case we use Asynchronous mode, the device will work too, but every reading of digital inputs will be slowly, because TimeOut of 1 sec will appear.

FT245RL Data Sheet:

FTDI chip is very fast, it allows more than 50 Read/Write commands per second to send.

Block's parameters:



  • CommunicatePerSec - the seconds per which the commands for Read/Write operations will be send to device. If this parameter is 0, the commands will be send per every DiscreteTime interval described in block Process.
  • FTDI_Device - this is a ComboBox with enumerated all the FTDI devices available on the current computer. The user has to select one of available FTDI devices.
  • Disable - If the diagram is started without connected device to computer, the process will be stopped automaticaly, because the device is not accessable. In this case if Disable parameter is checked, the process will be started without the device.
  • InvertOuts - the digital outputs of the device are presented as block's inputs. If the hardware after FTDI chip inverts the digital outputs, then it is more easy to invert all the signals, which enter into the block than to use NOT digital block to invert every input signal.
  • Mode - this parameter is very important, because some of the FTDI devices work well in different modes. Please read the difference between FT245BL and FT245RL chips above;
  • Purge -if the parameter is checked, then on every I/O operation, a SCADA software will purge the communication port and this will ensure that every command to device is processed. "Purge" decreases the communication speed with device. If the parameter is unchecked, the communication speed can be increased up to 1000 commands to device per second.


Block outputs:

  • CommunicationError - becomes to high level if the device does now respond to the computer's command;
  • OnRead - bocomes to high level when a data is received from the device;

The important output of the block is CommunicationError. Is case the device USB cable is very long, cable is disconnected or for other reason, some of the commands between computer and device can be not processed from device, then the described output will become to high value for 3 sec.

Demo - FTDI.nsm file:


Block GeigerCounterRH

Geiger Counter DIY Dosimeter Nuclear Radiation Detector DIY Kit from Radio Hobby Store:



  •  ComPort - index between 1 and 99 of PC COM Port on which the counter is connected


  • CPM - Count per minute