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digispark:tutorials:digicdc

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digispark:tutorials:digicdc [2015/01/08 00:19]
digistump created
digispark:tutorials:digicdc [2016/06/09 12:03]
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-===== DigiCDC - Digispark USB CDC Serial Library ===== 
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-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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-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>​ 
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-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 
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-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. 
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-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() 
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-You must install the driver for windows - it is part of the driver package found in the Digispark Arduino release. 
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-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! 
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-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. 
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-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. 
  
digispark/tutorials/digicdc.txt · Last modified: 2016/06/09 12:03 (external edit)