From 2419c049a3383d13d321e36a8dc885800911d744 Mon Sep 17 00:00:00 2001 From: marschap Date: Sun, 2 Dec 2007 17:23:35 +0000 Subject: [PATCH] extend ula200 doc; fix a few typos in contact chater --- docs/lcdproc-user/contact.docbook | 62 ++++++------ docs/lcdproc-user/drivers/ula200.docbook | 115 +++++++++++++++++++++-- 2 files changed, 142 insertions(+), 35 deletions(-) diff --git a/docs/lcdproc-user/contact.docbook b/docs/lcdproc-user/contact.docbook index 8c06456..500379c 100644 --- a/docs/lcdproc-user/contact.docbook +++ b/docs/lcdproc-user/contact.docbook @@ -11,14 +11,14 @@ in our efforts. -The main reason for that is the fact that we do NOT have all -the hardware people have writte. drivers for. Unfortunately -some developers have kind of vanished and don't react to mails +The main reason for that is the fact that we do not +have all the hardware people have written drivers for. +Unfortunately some developers have kind of vanished and don't react to mails from the mailing list any more. -So, as far as drivers are concerned we rely on YOU as testers. +So, as far as drivers are concerned we rely on you as testers. We have developed elaborate "coding in the dark" skills over the time. E.g. the CFontz driver has been updated and ported to 0.4.3 without the developers having the hardware. @@ -30,9 +30,8 @@ without the developers having the hardware. The LCDproc Mailing List -We are a bit lazy about the bug-tracking and whatever stuff -on SourceForge. So, please contact us directly through the mailing -list. +We are a bit lazy about the bug-tracking and whatever stuff on SourceForge. +So, please contact us directly through the mailing list. @@ -58,28 +57,33 @@ Before reporting this to the mailing list, please respect the following: -Your system should be more or less up to date. This does not mean -that you have to update from GNU/Linux kernel 2.0.x to 2.2.x or from 2.2.x to -2.4.x. But we would like to make sure that your problem is not related to a -known bug in the kernel or maybe your compiler. - -Especially LCDd might need certain privileges to execute -a command. Make sure LCDd HAS the rights to do so. - - -When experiencing problems with LCDd, make sure that your hardware is OK. -E.g. you should make sure that the wireing for your (in this case most -likely parallel) device is correct. - - -Make sure that you use the correct speed settings for your device. -Incorrect speed settings (baud rate) are most likely to produce garbage -scrolling on your display. -Refer to the specifications of your device. If your device needs a speed -setting that is not supported by LCDd send us a mail. -Make sure that you have modified the configuration file according -to your needs and that LCDd actually uses the configuration file. I.e. you might -have to run LCDd with the -c option + + Your system should be more or less up to date. This does not mean + that you have to update from GNU/Linux kernel 2.2.x to 2.4.x or from 2.4.x to + 2.6.x. But we would like to make sure that your problem is not related to a + known bug in the kernel or maybe your compiler. + + + Especially LCDd might need certain privileges to access a device. + Make sure LCDd has the required rights to do so. + + + When experiencing problems with LCDd, make sure that your hardware is OK. + E.g. you should make sure that the wiring for your (in this case most + likely parallel) device is correct. + + + Make sure that you use the correct speed settings for your device. + Incorrect speed settings (baud rate) are most likely to produce garbage + scrolling on your display. + Refer to the specifications of your device. If your device needs a speed + setting that is not supported by LCDd send us a mail. + + + Make sure that you have modified the configuration file according + to your needs and that LCDd actually uses the configuration file. + I.e. you might have to run LCDd with the -c + option diff --git a/docs/lcdproc-user/drivers/ula200.docbook b/docs/lcdproc-user/drivers/ula200.docbook index b1b02e3..d6c91b5 100644 --- a/docs/lcdproc-user/drivers/ula200.docbook +++ b/docs/lcdproc-user/drivers/ula200.docbook @@ -1,12 +1,116 @@ The ula200 Driver + +General + - This section talks about using LCDproc with LCD displays that use the - ULA-200 USB adapter for HD44780 drivers that can be obtained at - ELV. +The ULA-200 (short for German USB-LCD-Ansteuerung), +manufactured and sold by ELV, +is a small board that connects a HD44780-compatible display to the computer +using the USB interface. +Additionally it provides 6 digital inputs that can be used for keys. + +The ula200 driver controls this board supporting the features: + + + display on a single-controller HD44780 display + standard icons (heart, checkbox) + backlight control + input buttons + no horizontal or vertical bars + + + + + + + +Requirements + + +The driver uses libftdi, which again uses libusb +for communication with the device, so no kernel driver is needed on Linux, and the +driver can be used on other operating systems as well. + + + + When using a libusb based driver like IOWarrior, + LCDd needs to be started as root. + + + + + + On Linux, you have to take care that the ftdi_sio.kor + kernel module doesn't claim the ELV device. + If you didn't change the IDs in the kernel driver (ftdi_sio.c), + this should not matter. + + + + + + + + +Known problems + + +Sometimes the display hangs (the ACK response is not received) on shutdown. +Reconnect the display in that case. +Please do the same if it hangs while starting up. +The latter only happens if it was not the first time LCDd +talked to the display. + + + + + + +Implementation note +(by the driver's author Bernhard Walle) + + +The ULA-200 talks a text protocol which allows to display text using a +high-level language, i.e. +STX s len +char0 char1 ... ETX. +It also allows low-level register access to the HD44780. +So in theory, it would be possible to write a connection type for the +hd44780 driver and let the hd44780 core do the rest. +I tried this. It was slow and didn't work with user-specific characters +(the hd44780 frequently changes this characters which seems to confuse the +microcontroller, at least I cannot explain why it didn't work, there was +garbare). + + + +So I wrote a separate driver, the ula200, which uses +the high-level language and should work for displays with all sizes. +I only tested 20x4, so maybe for other sizes the positioning code may be adapted. + + + +As I mentioned, there were problems with frequently changing the +user-definable characters. +I also tried to implement bar code in the ula200 driver +with similar effects. +I gave it up because I don't need it personally and it can be done later. +However, standard icons are implemented. +The user-definable characters are set in startup and are not changed. +This works like a charm. +It is not possible to use character 0 with the high-level language +(or at least it isn't documented how to escape it). +It could be done with hd44780 code, but I replaced the character with +a standard character which looks good. + + + + + Configuration in LCDd.conf @@ -63,7 +167,7 @@ Enter and Escape. - The following it the built-in default mapping hardcoded in the driver. + The following table lists the built-in default mapping hardcoded in the driver. @@ -97,8 +201,7 @@ You may leave it unchanged if you have a standard keypad. - You can change it if you want to report other keystrings or have a non - standard keypad. + You can change it if you want to report other keystrings or have a non-standard keypad.