Messages in this thread | | | Date | Fri, 3 Jun 2005 22:50:14 +0200 | From | Henk <> | Subject | Re: [RFC] new 7-segments char translation API |
| |
On Wed, Jun 01, 2005 at 02:33:11PM +0200, Clemens Koller wrote: > Hello, Henk! > > >1 - Notation > > > >Make things potential interoperable, your character sets will be > >portable to other LCD devices. > > > > +-a-+ > > f b > > +-g-+ => encodes to => MSb 76543210 LSb > > e c gfedcba > > +-d-+ bit7 is reserved. > (x) > > Bit7 is propably useful for the decimal point (x)? > Well, that's how I used it some time ago. > Hi Clemens,
I think it could. However for conveniance I implemented it as a seperate addressable entity.
For userspace I want things to be simple, just a simple echo should be sufficient to manipulate the LCD:
For example:
echo -n "3 A 1.0 0 0" > /sys/.../line1
in order to set the lcd. In order to read back the contents of the lcd:
cat /sys/.../line1 8.8.8.8.8.8.8.8.888 <= format string, see below 3 A 1.0 0 0 <= contents
When the dot is encoded in the digit you would lose a digit when a dot is printed. In a two segment display with dots "1.0" can not be printed.
I don't want kernelcode trying to decide if it should collapse "1." in a single digit or not. These implicit functional rules are always a pain in the ass when not implmented at the right level. And don't belong in the kernel.
Best regards, Henk
/* Format string description: * * From a user space perspective the world is seperated in "digits" and "icons". * A digit can have a character set, an icon can either be ON or OFF. * * Format specifier * '8' : Generic 7 segment digits with individual addressable segments * * Reduced capabillity 7 segm digits, when segments are hard wired together. * '1' : 2 segments digit only able to produce 1. * 'e' : Most significant day of the month digit, * able to produce at least 1 2 3. * 'M' : Most significant minute digit, * able to produce at least 0 1 2 3 4 5. * * Icons or pictograms: * '.' : For example like AM, PM, SU, a 'dot' .. or other single segment * elements. */
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |