From: "Steve Simon" <steve@quintile.net>
To: 9fans@9fans.net
Subject: [9fans] small VFD display
Date: Wed, 6 May 2015 10:52:30 +0100 [thread overview]
Message-ID: <304bae18668f389aae7eccd289462cda@quintile.net> (raw)
Hi,
I want to drive a small (180x32 pixel) VFD display from plan9.
It talks i2c and can be driven as a text or graphics device.
One irritation is it aligns bitmap bytes verticaly. i.e. the display's
memory map appears to be a tradational 32x180 pixel display.
I am going to talk to this from a raspberry pi.
I see several options:
resurect a small graphics library I wrote in the last milenimum, this
knows about the weird layout but only supports rather nasty fonts and
very simple windowing.
talk text only to the display - again rather nasty fonts.
draw the images in a plan9 window under rio. A seperate process
which reads /dev/wsys/n/window, transforms it and sends it to the VFD.
I would also need a backing buffer in VFD layout so only the changed
bytes are sent.
Is there another way?
Could I run the plan9 graphics subsystem in a stand alone app rather
than involving the kernel?
I think I can but are there any examples of this?
Though this sounds nice, is it worth the hassle of doing this?
Any opinions?
-Steve
next reply other threads:[~2015-05-06 9:52 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-06 9:52 Steve Simon [this message]
2015-05-06 13:30 ` yy
2015-05-06 14:31 ` Steve Simon
2015-05-06 14:13 ` Steven Stallion
2015-06-09 4:56 ` Ethan Grammatikidis
2015-06-09 10:10 ` lucio
2015-06-09 18:03 ` Robert Raschke
2015-06-09 18:34 ` Ethan Grammatikidis
2015-06-10 4:43 ` lucio
2015-06-10 4:43 ` lucio
2015-06-10 15:58 ` Giacomo Tesio
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