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digispark:tutorials:digicdc [2015/01/15 09:05]
digistump
digispark:tutorials:digicdc [2016/06/09 12:03]
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-===== DigiCDC - Digispark USB CDC Serial Library ===== 
  
-The DigiCDC library allows the Digispark or Digispark Pro to appear to a computer as a Virtual Serial Port when connected by USB. This makes it appear just like a standard Arduino and allows the use of the Serial Monitor built into the Arduino IDE. 
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-DigiCDC was based on the V-USB project and avrcdc project - the first version (the hard work) was created by ihsan Kehribar (http://​kehribar.me) and then turned into an Arduino library and refined by Erik Kettenburg (Digistump) 
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-=== Limitations and Usage === 
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-The DigiCDC library is based on V-USB - because the Digispark does not have hardware USB support. This presents some unique limitations in how it works - outlined below: 
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-  - You must explicitly include the DigiCDC library - by placing the following at the top of your sketch <​code>#​include <​DigiCDC.h></​code>​ 
-  - It uses a lot of RAM - half of the Digispark'​s RAM - so only include it when needed and watch your RAM usage. You can wrap strings in F() (ie. SerialUSB.print(F("​test"​)) ) to put the string in flash memory instead of RAM 
-  - You use it the same as Serial on an Arduino but with SerialUSB instead (ie. SerialUSB.read() instead of Serial.read() ) - The Pro also has Serial defined - but that refers to the hardware Serial port on Pins 6 and 7. 
-  - The begin statement does not need a baudrate - it is a CDC device so it does not have a set baud rate - just use SerialUSB.begin() 
-  - You must install the driver for windows - it is part of the driver package found in the Digispark Arduino release. ​ 
-  - It is slow - it transfers data very slowly - because it is a low speed USB device doing the job of a Standard speed device - and doing it all virtually without actual hardware support! 
-  - Like all of our V-USB libraries you must use its delay function instead of delay() - so use SerialUSB.delay() when you need a delay in your code. 
-  - SerialUSB.delay() or SerialUSB.refresh() must be called every 10ms or less in your code if no other SerialUSB call is made in that code. 
-  - Advanced experimentation:​ You can use SerialUSB.setDelay() to adjust the delay between each character written to the host (in ms) - 45 is the default, some people have luck with as little as 9ms. 
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-=== Examples === 
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-Examples can be found in the Digistump Arduino release (1.5.8C or higher) under File->​Examples->​DigisparkCDC 
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-=== Android Devices === 
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-DigiCDC can be used to make the Digispark appear as a Serial device to an Android device when attached to an Android device'​s OTG port. The device must support Serial/CDC devices via OTG 
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-Android App Examples (using phonegap/​cordova and editable with only working knowledge of javascript and HTML): 
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-https://​github.com/​digistump/​Digispark_Cordova_CDCLED 
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-https://​github.com/​digistump/​Digispark_Cordova_CDCEcho 
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-Phonegap/​Cordova Plugin used in the examples above to connect to a DigiCDC device: 
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-https://​github.com/​digistump/​DigiCDCPhonegap 
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-(plugin use FTDriver by Keisuke SUZUKI ​ https://​github.com/​ksksue/​FTDriver) 
digispark/tutorials/digicdc.txt · Last modified: 2016/06/09 12:03 (external edit)