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sparkfun / Serial7SegmentDisplay

Example code and board files for the Serial 7 Segment Display.
https://www.sparkfun.com/products/11629
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Display something on power up #16

Closed josephernest closed 9 years ago

josephernest commented 9 years ago

I'm using the 7segment display with a raspberry pi. During the Linux booting time (~15 seconds), the 7segment display displays nothing.

Is it possible to show "___", "----" once it is powered up?

So the user will know the system is "booting".

How to do this?

jimblom commented 9 years ago

Sure, this is a relatively simple modification. The four variable assignments starting here set what the display shows on start-up.

For example, to make the display show "----", swap in these four lines of code:

display.digits[0] = '-';
display.digits[1] = '-';
display.digits[2] = '-';
display.digits[3] = '-';
josephernest commented 9 years ago

So do you mean it should already display something on power up? (it seems, in your code, that 1234 should be displayed on power up, or am I wrong?).

I just tried by connecting +5V and GND only (and no serial, no I2C), but nothing is displayed.

When exactly should these default letters be displayed? As soon as +5V arrives ? or is there another trigger for the "startup"?