IRK! Infrared Remote USB Keyboard Files

HISTORY  - Date     Ver   By  Reason (most recent at the top please)
           -------- ----- --- -------------------------------------------------
           20131230 3.04  AJA Updated the LCD package to have 3 mm mounting
                              holes instead of 2.5 mm.
           20131229 3.03  AJA Added local IRK! functions to turn on and off the
                              4066 analog switches (PWR, RST and AUX). The
                              existing code only asserted them for 250 ms.
           20131228 3.02  AJA SMT version now works at 48 MHz. It will also work
                              at 24 MHz but the mikroProg Suite software has a
                              bug at the moment which prevents setting the 
                              configuration bits appropriately.
           20131210 3.01  AJA Added a new Surface Mount Technology (SMT) version
                              which uses a PIC18F25K50 and a 4066 quad analog
                              switch. Not actually tested yet. The original 
                              Through Hole Technology (THT) version remains
                              unchanged at version 2.11.
           20131126 3.00  AJA This version is for a PIC18F25K50 which has
                              an internal oscillator that can drive the USB
                              module - so no crystal is needed anymore.
           20130413 2.11  AJA Recompiled for MikroC 6.0 which appears to be
                              case-sensitive now (for example, library routines
                              must be spelled properly).
           20130213 2.10  AJA Detect whether any buttons are pressed at power
                              up (or, equivalently, an ICSP programmer is still
                              plugged in) and display a "Release Buttons!" 
                              message until the situation is rectified.
                              Enabled USB Full Speed mode, so IRK will run in
                              either Full Speed or Low Speed mode. Before IRK
                              only worked in Low Speed mode.
                              Recompiled with MikroC v5.80.
           20121213 2.09  AJA Reserved RAM Bank 4 for USB use only. Corrected
                              button press handling when setting backlight
                              delay, device address or selecting usage.
                              Added ability to set the GUI key flag by pressing
                              and holding the CTL key. The GUI key is a generic
                              name for the Windows key, the Apple (Command) key,
                              or the Super key on Linux systems.
           20121211 2.08  AJA Saved a huge amount of RAM and expanded text
                              descriptions dramatically by copying text from
                              ROM to RAM as it is needed (to display on the LCD
                              for example). This is done using the _TEXT
                              function and by specifying "const" on all functions
                              that return a string.
           20121025 2.07  AJA Added extra Consumer Device function descriptions.
                              These are optional, but make IRK easier to use.
           20121020 2.06  AJA Increased the WIDTH_ERROR_MARGIN from 100 to 300
                              microseconds (that to half the smallest pulse
                              width). This has fixed the sensitivity problem.
                              Also added a debug on/off local IRK function.
                              Now displays graphic symbols for up/down/left/
                              right/pause and backslash on the LCD.           
           20121009 2.05  AJA Fixed the pulse width check introduced in 2.04.
           20120813 2.04  AJA Reduced training burst interval to conform with
                              the TSOP4838 data sheet. Training burst reduced
                              from 9000 to 1000 microseconds. Silence after
                              training burst reduced from 4500 to 600 microseconds.
                              Added extra pulse width checks.
           20120312 2.03  AJA Repackaged the lot into a single zip file
           20120310 2.02  AJA USB buffer overwrite problem seems to have been
                              fixed in MikroC Pro v5.40 so I've removed the
                              workaround of using a 2nd buffer. Fine tuned the
                              USBdsc.c settings - use a slower polling rate and
                              a few other minor changes.
           20120308 2.01  AJA Allow local IRK! functions such as Backlight On
                              to be programmed to a remote control button.
           20120215 2.00  AJA Rewrite to support Consumer Devices usage page
                              and other usage pages in the future
           20101122 1.19  AJA Detect USB ready using HID_Write (not HID_Read)
           20101120 1.18  AJA Added "Init USB" function
           20101106 1.17  AJA Use LATC for outputs
           20101023 1.16  AJA Don't try to send keystroke when USB is not ready
           20101007 1.15  AJA Workaround USB send problem by using 2nd buffer
           20100923 1.14  AJA Detect when power good from USB then init USB
           20100911 1.13  AJA Recompiled with MikroC v3.8 (new USB interface)
           20100828 1.12  AJA Added button debounce delay
           20100810 1.11  AJA USB D+ and D- swapped (doc updated)
           20100806 1.10  AJA LCD backlight polarity swapped (doc updated)
           20100725 1.09  AJA Added LCD backlight control
           20100619 1.08  AJA Added reset switch and power switch logic
           20100616 1.07  AJA Use HS crystal instead of crystal oscillator
           20100531 1.06  AJA Recognised broadcast address
           20100522 1.04  AJA Added "set address" facility
           20100519 1.03  AJA Added System Control (power) codes
           20100501 1.00  AJA Initial version (using MikroC v3.2)