README_LCD

Some project history
====================

This software is based on the sd2iec-0.10.3 software by Ingo Korb. 
First the LCD functionality made by Draco for an older version was added by Seanser.
Then andi6510 added support for DOGM LCD modules based on a ST7036 controller
and did some tidy up work by removing all remaining non-LCD related differences 
between Seansers version and the official sd2iec-0.10.3.

This software was tested on an ATMEGA1284p microcontroller with a ST7036 based 
DOGM162 module and another HD44780 based module (exact type unkonwn).


New files added on top of sd2iec 0.10.3
=======================================

lcd.c - low level LCD driver - initial version from draco, andi6510 added lcd auto detection and st7036 support
lcd.h - low level LCD driver interface
display_lcd.c - high level LCD functions - initial version from draco, andi6510 added contrast setting for st7036
display_lcd.h - high level LCD functions interface
config-larspLCD - configuration for LarsP hardware with LCD attached
README_LCD - this file



Modified files of sd2iec 0.10.3
===============================

buffer.c - display "READY" when the last buffer has been closed - seems more a hack and should be replaced with a proper solution
d64ops.c - display "LOAD" and "SAVE" when files are accessed in a D64 image
doscmd.c - display various messages on each command - add LCD specific X-commands: XT XA XG XX XC
eeprom.c - add LCD-contrast setting to eeprom storage
errormsg.c - display current error message
fatops.c - display current directory
main.c - initialise LCD functions, display welcome screen, debug output of detected LCD type
Makefile - added files display_lcd.c and lcd.c to build process, added prerelease tag LCD



Additional Commands available via IEC
=====================================

XT* Text Commands
-----------------

The display can be accessed from the c64!
Use commands "XT1" and "XT2" to send text to display line 1 or 2.
The addressed line will be cleared before text is printed.

Example 1 - send "Lightyears ahead!" to line1:

OPEN15,8,15,"XT1Lightyears ahead!"

The "XTC" command allows to send a control code followed by data, which makes it possible
to program the display from the C64 side, e.g. define own characters.

Example2 - clear the screen:

OPEN15,8,15,"XTC"+CHR$(1) will clear the screen.

Example 3 - define a special character with a "heart" (line 2) and print it 3 times (line 3):
1 OPEN15,8,15
2 PRINT#15,"XTC"+CHR$(64)+CHR$(27)+CHR$(31)+CHR$(31)+CHR$(14)+CHR$(4)+CHR$(0)+CHR $(0)
3 print#15,"XT1"+CHR$(8)+CHR$(8)+CHR$(8)
4 CLOSE15


Display About Message
----------------------

The XA command shows a small about message:

Example:

OPEN15,8,15,"XA"

Display Greetings & Credits
---------------------------

The XG command shows the greetings and credits:

Example:

OPEN15,8,15,"XG"


Undocumented experimental feature
----------------------------------

The XX command is not documented. It might cause skynet to
link all computers together to play a game of global
thermonuclear war.

Maybe your C64 is not connected to skynet, so you'll give it a try.
Good luck!

Example:

OPEN15,8,15,"XX"


Setup LCD contrast (only for ST7036 based displays)
---------------------------------------------------

The XC command changes the display contrast on a ST7036 based display
Valid contrast values  go from 0 to 63. 

Example:

OPEN15,8,15,"XC 40"

Note:
Once contrast is adjusted properly the setting can be saved with the XW command!



LCD Hardware
============

Every HD 44780 or ST7036 compatible displays (2x16 or 2x20 chars) should work
The display is accessed in 4-bit mode.

Different pinouts have to be used depending on the hardware variant
of the SD2IEC / MMC2IEC device:

sd2iec V1.4 by Shadowolf (sw1 variant)
MMC2IEC by Lars Pontoppidan (larsp variant)
-------------------------------------------
(original design, also used by PCBs from Peter Sieg)

Display Atmega
RS PB0
RW PB1
E PB2
DB4 PC4
DB5 PC5
DB6 PC6
DB7 PC7


sd2iec V1.6 by Shadowolf (sw2 variant)
--------------------------------------
ATTENTION: I have not yet tested this pinout so it might be possible that it is not working.
At least it will be hard to solder the display to PB0,PB1 and PB3 if using a TQFP44 mcu.

Display Atmega
RS PB0
RW PB1
E PB3

DB4 PC4
DB5 PC5
DB6 PC6
DB7 PC7

For other variants please feel encouraged to change the lcd.h to suit your needs.


Credits
=======

Draco who did most of the LCD functionality
Seanser who started the initial porting from version 0.8 to 0.10.3
Ingo Korb alias for his great SD2IEC firmware.
Shadowolf for his outstanding hardware designs running the SD2IEC firmware.
Lars Pontoppidan for creating the MMC2IEC in the first place.
Jim Brain & ChaN for basic code like IEC routines and FAT driver.
Commodore for the good times.

Licence
=======

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License only.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA