Andres Mata Posted April 24, 2016 Report Share Posted April 24, 2016 Hi All, I just got my new Papilio Pro and I was trying the examples from DesignLab. I've been playing around with different examples (Audio, VGA, etc.) and they work fine. But when I run any of the VGALiquidCrystal examples thye are just displaying two rows of green squares but no text in there. The following screenshot (LCD_Demo.jpg) shows the results I get from the "LCD_Demo" example. The VGA demos work fine (see screenshot - VGAHelloWorld.jpg) Just fyi, I'm not using any Wing, I'm just connecting 6 pins in the CH Wing2 port to the VGA cable (V-SYNC, H-SYNC, R, G, B, GND) as in the screenshot - DirectPinout.jpg. I am wondering if I am missing anything here. Do I require to connect anything else? Working with a real Liquid Crystal display needs to connect a couple of signals (rs, enable, data, etc.) but is it also necessary in this modified version? If not, what do the pins in the VGALiquidCrystal() call mean? Regards, Andres Quote Link to comment Share on other sites More sharing options...
Jack Gassett Posted April 25, 2016 Report Share Posted April 25, 2016 Hello Andres, You are most likely missing the Character Map which needs to be connected to a Wishbone slot in your circuit. The following code defines which Wishbone Slot it should be connected to: VGA.begin(VGAWISHBONESLOT(9),CHARMAPWISHBONESLOT(10)); Jack. Quote Link to comment Share on other sites More sharing options...
Jack Gassett Posted April 25, 2016 Report Share Posted April 25, 2016 This is what the example LCD_Demo's circuit looks like: You need to make sure that the circuit you are using has the VGA Char Map included. You should be able to just load the circuit for the LCD_Demo to your board, as long as your VGA pinouts match what a VGA Wing connected to CH would be. Jack. Quote Link to comment Share on other sites More sharing options...
Andres Mata Posted April 27, 2016 Author Report Share Posted April 27, 2016 Ok, I know what's happening: I just wired one bit per RGB channel (like the VGA wing v1.0) but the LED library needs both bits per channel. As soon as I fed the second bit signal to the RGB channels the letters showed up. Quote Link to comment Share on other sites More sharing options...
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