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Configuring the I/O pins


Open the ULINKplus dialog View - Analysis Windows - ULINKplus.

I/O Dialog The I/O section shows how the I/O pins are configured:

  • Pin - Displays the pin number
  • Function - Displays the current function set that is applied to the I/O
  • Out - If the function is "Digital Output", you can set the output to high by checking the box. Otherwise the output is low. For Pin 7, when configured for Analog Output, the pin voltage displays.
  • In - Displays the current I/O voltage level if configured to "Digital Input"


Command window

The I/O pins are configured, accessed and controlled using ULINK Virtual Simulation Registers (VTREGs). The I/O VTREGs are defined below:

VTREG Type Description
Mode setup
ULINK_DIR integer Set input or output direction. Bit clear = input, bit set = output
ULINK_AMODE integer Set digital or analog function. Bit clear = digital I/O, bit set = analog I/O
Digital I/O
ULINK_IN integer Reads digital input pins (also returns the physical level on output pins)
ULINK_OUT integer Sets digital output pins (pins configured as input with ULINK_DIR are not affected)
Analog I/O
ULINK_AINn float Voltage level at analog input. n=4..7, requires pin configuration for analog input
ULINK_AOUT7 float Voltage level at analog output, requires pin configuration for analog output
ULINK_3V3 integer Turns +3.3V Out pin on or off. 1=On, 0=Off

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