[Lcd4linux-devel] Graphics support for Cwlinux

[Xavier V. <xav...@fr...>]

Hello Michael, hello list.

I feched the datasheet of the CW12232 display, and you're right, Michael
:/ It's impossible to have a 122x32 graphic zone with a decent
framerate.
As the command to put one pixel is at least 5bytes long and the
transfert rate is 19200, it takes about 30seconds to write all the
display :/ But there are some interesting features :
- The display can handle text, bars (without user characters) and
graphics togethed, so we can have some text, draw bars and display some
pixmap with the rest of the bandwith.

- It support also 'inverted text', that's a good thing, for example if a
temperature hits a predefined maximum value, you should add such and
option to the text widget (and use it if the display supports it)

- Time based graphs will be somewhat easy to do, as we can draw
rectangle of 2 or 5px width and programable height, so the graph is made
of a combinaison of 2px large rectangles

- The new version has 2 GPOs (to put a relay) and a relay ! The relay
may be used, according to Cwlinux to emulate a pulse button (like the
'sleep button' never avaible on PC cases or even the reset button {but
it's not very useful to linux users ;) } ).

- There's also 2 GPIs, I don't know if I will use them (maybe with a
light sensor to activate backlight when there's not enough light).

- And MOST important of all, a keypad ;)

Do you think it's possible to implement a time-based graph widget, and a
sort of 'fixed pixmap' widget (but which format to use for images ?) ?
Moreover, GPIs are read on demand, so should we write a
plugin_cwlinux_gpi or add the function within the drv_cwlinux ? I don't
know your position on this point.

There's still the problem of keypad handling, as the display sends the
keys directly, the driver should always be able to read this values.
Where can we implement this read ? directly drv ? plugin ? keypad.c ?

Bye !
-- 
Xavier VELLO <xav...@fr...>

PS: I didn't have any answer from the cwlinux staff :/