A bit like this:- Quote What USB driver does Arduino use It is a simple serial port, nothing fancy.The desired goal would be uploading an Arduino sketch with the Firmata functionality so that the Arduino could be completely controlled by the host computer using the LabVIEW interface to enter Firmata-commands (to activate relays, run a bipolar stepper motor, read values from an encoder, etc).
Sartorius Labview Driver Does ArduinoSartorius Labview How To Implement ItDoes anyone have experience with the Firmata protocol and how to implement it using VISA The old Firmata home-page offered one example of a LabVIEW program using the Firmata protocol; however, it is only scanning the Firmata report for the analog pin voltage values. It does show how to convert the corresponding hexadecimal values to the LSB and MSB bits but I am unsure how to use this. I have only progressed by using the vvvv software and seeing how pin values and pin modes are encoded to the Firmata protocol. Using the Standard Firmata uploaded on the Arduino, I can successfully activate LEDs using digital or analog (PWM) commands through the vvvv interface. If I change my pin modes and commands to be all digital, I can successfully activate all LEDs using my LabVIEW interface and standard Firmata sketch. I am currently trying to communicate to the microcontroller through a USB serial connection using LabVIEWs VISA to write commands. As mentioned previously, I can successfully command digital pin values but cannot command pin values by PWM. As I understand it, the Firmata protocol loosely follows MIDI where command bytes are 8 bits and data bits are 7 bits. Supposedly, there are some commands that can accommodate more bits but I have not successfully applied them. Individual examples (0x is the hexadecimal radix) 0xF4 0x08 0x01 PinMode for pin 08 is set as a digital output 0xF4 0x03 0x03 PinMode for pin03 is set as a PWM output (I think) 0x90 0x00 0x00 port 0 of Arduino has LOW Outputs on all its pins 0x90 0x08 0x00 port 0 of Arduino has one HIGH output on pin 03 0x90 0x08 0x00 0x91 0x11 0x00 port 0 has one High output on pin 03; port 1 has HIGH outputs on pin 08 and pin 12 (which does work) 0x90 0x00 0x00 0x91 0x11 0x00 0x92 0x00 0x00 0xE3 0x01 0x7C 0xEB 0x00 0x 00 Port 0,1, and 2 have LOW outputs on all digital pins, pin 03 has some PWM output (somehow corresponding to 255); pin 11 has no output The last example does not activate LEDs using the analog write command. I have attached some supplementary material if anyone is interested including my programs that activate digital pins only and tries to activate digital and analog pins. Sartorius Labview Windows 7 Home PremiumReferences Firmata protocol Firmata home page (old) Firmata labview example Firmata download Vvvv download Hardware Dell XPS 8300 Intel Core i5-2320CPU 3.00GHz 8.0GB RAM Arduino Uno R3 SMD edition Arduino Motor Shield R3 Software LabVIEW Developmental System 8.6 NI-VISA version 5.0 Operating System: Windows 7 Home Premium, 64-bit Arduino IDE version 1.6.5 Standard Firmata, copyright 2015 Jeff Hoels vvvv version 45beta34.1, x64 vvvv addonpack version 34.1.0 Firmata version 2.6.1. Would anyone please share their experiences using the Firmata-commands from a software interface that was different from the Arduino IDE I am trying to upload a sketch to the Arduino microcontroller so that it used the full functionality of the Firmata library (activating analog and digital pins) but relied on the Firmata commands to be transmitted to the Arduino through the USB serial connection. All the rest is down to LabView, it communicated to the Arduino through the serial port which is the USB as far as the Arduino is concerned. Any data manipulation has to be done in LabView, like turning a MSB and LSB into a number. The present state of affairs is that I am trying to decipher what VISA commands to initiate so I can correctly write and read the buffer from this serial connection. This has become quite infuriating because while I am reading VISA user manuals, I can easily communicate these hexadecimal commands to the Arduino using a different, unsupported software interface called Sartorius COM Helper. This leads me to believe that it is mainly a format issue that requires just a slight tweak of the standard parameters that LabVIEWs VISA uses to establish a serial connection. But. I have NO idea how Sartorius COM helper has established a serial connection with the Arduino What USB driver does Arduino use And how can I view it or understand how it works Maybe, if I understood how it works; I could determine what I need to do in LabVIEW. Could you explain further or direct me to some literature about the conversion of two 7bit bytes (MSB and LSB) into a number Why MSB multiplied by 256 Thank you for the reply and thank you for reading this, -Zach. If they are then simply combine them with:- number (MSB 128) LSB It is all to do with powers of two and binary numbers, you are simply shuffling the bits from the two smaller numbers into successive bits of a larger number. As a byte can only hold numbers between 0 and 255 then one in the most significant byte is worth 256 of the numbers in the least bit.
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