Graphic LCD - Font table in external EEprom

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GrahamGo

Senior Member
I am playing with a graphics LCD, and can see that I really need more Font Table space than the internal EEprom provides (currently using a 14M2). I assume that I can easily add (lets say) a 16kbit I2C. I see that there are existing I2C procedures provided. My question:- Is it possible to load this external eeprom's Font tables with the same ease as this? :-

eeprom 0, (0x7F, 0x09, 0x09, 0x09, 0x01)

If not, how would one get the Font tables into the external eeprom? I can see making the Font array in flash space and then transferring to the eeprom - is this the way?

Also somewhere I read and I cannot find it again. That a certain I2C EEprom manufacturer is preferred due to I2C timing constraints. Sticking my neck out I am guessing Microchip?
 
W

westaust55

Moderator
It will depend in part which gLCD you are using as to the format for the font data.
For type typical 128x128 (or 132z132) 4096 colour gLCDs as used in many Nokia phones such as the 6610, 6610i and 6100 (and many more) see the work I am doing here:
http://www.picaxeforum.co.uk/showthread.php?20181-Using-the-Nokia-128x128-4096-colour-gLCD-with-PICAXE-chips
See post 10 and post 11 for a couple of font sizes which I posted code to write to an external EEPROM.


If you are using a typical monochrome gLCD (as from Siemens A55, Nokia 1100, Nokia 2280, Nokia 3310) then have a look at the files I posted here (see post 14 and others):
http://www.picaxeforum.co.uk/showthread.php?10014-Siemens-A55-C55-LCD-graphics-display/page2

The monochrome have the data on a column basis whereas the colour displays have the data orientated on rows.


If nothing else and youa re using a different gLCD all together then at least these files shown you how I do it.
 
G

GrahamGo

Senior Member
Yes I am playing with a 3310 but need more characters plus math symbols. Strange I tried the Forum search, both normal and advanced for quite some time. I see one example that you pointed at is from 2008. But I can't seem to search earlier than 2011. even now that I know that the threads exist I cant find them...... Hum...

I have briefly looked at the one example, the "Code to put 5x7 font in external EEPROM". I see there that you basically wrote a program solely to fill the external Eeprom with font and keyboard data ie. Hi2cout 552, (0x00, 0x1c, 0x22, 0x41, 0x00) ; ( ; etc etc. So this fits in with what I was thinking, I haven't looked at the other examples yet, but I assume that its a common approach.

I am living in what could be called the backwoods of Mexico, and getting parts is a bit slow. Now I think I have the reassurance, to get some EEproms on order! Thanks its greatly appreciated.

Completely off subject. Yesterday I was playing Volleyball with some friends. I happened to look up and saw five UFO's in tight formation slowly traversing a bright blue morning sky. They were close enough to see some detail (a triangular front with a rounded rear section, no wings or obvious propulsion in sight). I saw them for about 4 seconds, then they turned slightly and accelerated away at tremendous speed in different directions. Luckily I had been able to point the objects out to the friends around me and five others confirmed seeing the same event. We then got back to our Volleyball - as you do....
 
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pleiser

pleiser

Senior Member
GrahamGo said:
... Strange I tried the Forum search, both normal and advanced for quite some time. I see one example that you pointed at is from 2008. But I can't seem to search earlier than 2011. even now that I know that the threads exist I cant find them...... Hum...
Click to expand...
you need to select any date for advacded search- additional options- find posts-first option box
for regular forum viewing you need to scroll to the bottom of the page where it says thread display options and select show threads form the beginning (mine defaults to last day every time) and click on show threads
 
G

GrahamGo

Senior Member
pleiser said:
you need to select any date for advacded search- additional options- find posts-first option box
for regular forum viewing you need to scroll to the bottom of the page where it says thread display options and select show threads form the beginning (mine defaults to last day every time) and click on show threads
Click to expand...
Thank you. Strange but in the advanced search originally it would only give search results for 2012 & 11. I changed some settings and it started to provide search results for posts going way back. Then I reverted back to the original settings and it still searches way back. So something got changed, and it now works..... My "Thread Display Options" defaults to "from the beginning" so I am OK on that score.
 
G

GrahamGo

Senior Member
This is excellent, so much info on this Forum. I think everything has been done - nothing left to invent!

I need about 350 bytes of none volatile, now I wonder if I could use the internal eeprom plus a bit of the program flash area. Back to searching the Forum before I try my own solution!
 
W

westaust55

Moderator
You can with some programming skills to switch use both internal EEPROM and TABLE memory which are non-volatile.
Use EEPROM and TABLE directives to establish the data (which is downloads at th time the program is downloaded).
Then use READ and GET to access the data from the respective memory areas.
 
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