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diff --git a/README.Crystalfontz b/README.Crystalfontz new file mode 100644 index 0000000..4c76b45 --- /dev/null +++ b/README.Crystalfontz @@ -0,0 +1,44 @@ + +This is the README file for the Crystalfontz display driver for lcd4linux + +This driver supports the 632/634 LCD-Modules from Crystalfontz, but should +work for the 626 and 636 modules too. The 634 is a 20x4 character display, +while the others only display 16x2. I've written the driver using a +634 module. + +The driver understands the following configuration parameters: + +Display: any of 626, 632, 634 and 636. + +Port: serial device (i.e. ttyS0) the LCD module is connnected + to. + +Speed: any of 1200, 2400, 9600 and 19200. By default, the driver + uses 9600 which is the speed the LCD modules are hardwired + at. If your module works at a different speed than 9600, + use this parameter. Otherwise omit it (i.e. omit it when + you have a 634). + +Backlight: controls the backlight brightness. Quote from 634.pdf from + the Crystalfonts-Webserver[1]: "0=OFF 100=ON. Intermediate + values vary the brightness. There are a total of 25 possible + brightness levels." + +Contrast: controls the contrast settings. Quote[1]: "0=very light, + 100 = very dark. 50 is typical. There are a total of 25 + possible contrast levels." + + +Known bugs: +When you draw a bar over a previously drawn textfield, the white portion +the bar will not erase the text. Only when the black portion of the bar +has reached the full bar length, the text will be erased. I did not bother +to implement that, since in lcd4linux, the whole display-screen is erased +prior to switching to a different 'screen'. Implementing this feature would +just add to program-overhead. Yes, you guessed it: I did not use the "bar"- +command that comes with the LCD-module, but wrote my own instead. +lcd4linux also supports "split-" or "dual-bars" (two bars in one segment), +which are not available on the Crystalfontz firmware. + + [1] http://www.crystalfontz.com + |