Date: Sun, 26 Nov 2000 20:06:28 +0300 From: "Artem Koutchine" <matrix@ipform.ru> To: <hardware@freebsd.org> Subject: LCD contrast control on extanded temperature lcds Message-ID: <000701c057cb$38b15fe0$0c00a8c0@ipform.ru>
next in thread | raw e-mail | index | archive | help
Hi! I have managed to attach LCD (HD44780 compatible from Powertip. PC2004-B model). However, the contrast is too bad and i cannot even start developing software to control it the way it need. (super quite home mp3 player, tired of working fans :)). It is an extended tempretaure unit (-20C - 75C) and it needs voltage from GND to -7V on Vo (contrast control pin). I cannot figure out how to get -7V from pc power supply. The other thing, is that LED backlight is heating badly. I thought it has resistor built-in, but it seems as it does not. What resistor should i use there for +5V line (typical current for the LED is 260mA). I hope, someone whould help, because i am a programmer and not very good at MAKING hardware. Regards, Artem To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?000701c057cb$38b15fe0$0c00a8c0>