Tixy's Source Code

C++ and Forth source code.

All code is distributed under the terms of the MIT License which means that you can use and modify it for any purpose.

The code has only been tested on 32bit little-endian targets but has been designed to be word size and endian agnostic; please let me know if it doesn't work on your system.

C++ source is commented using Doxygen style comments and is formatted with tab stops every four characters.

If you have any comments, please feel free to contact me.

Common

All C++ code below requires this header file which provides type definitions and helper macros which aren't part of standard C++.

• common/common.h
• Documentation
• common/test/test.h - Definitions used for test code.

Utilities

String Formatting

Extensible classes for producing formated C strings. This also contains implementation of the C standard library functions: vsprintf, sprintf, vsnprintf and snprintf.

• utils/stringf.h
• utils/stringf.cpp
• Documentation
• utils/test/stringftest.cpp - Test code.

Bit Vector

Classes for constructing and manipluating a bit-vector (array of bits).

• utils/bitvector.h
• utils/bitvector.cpp
• Documentation
• utils/test/bitvectortest.cpp - Test code.

Maths

This code is targeted at CPUs without hardware support for division or floating point. It has been optimised for ARM CPUs but should be suitable for other RISC architectures.

Fixed-Point Maths

32 bit fixed-point maths implementation, including multiplication, division, square-root, trigonometric and logarithm functions.

• maths/fix.h
• maths/fix.cpp
• Documentation
• maths/test/fixtest.cpp - Test code.

3D Vectors

Routines for handling 3 dimensional points, vectors and matrices. This uses the Fixed-Point Maths routines above.

• maths/vector3.h
• maths/vector3.cpp
• Documentation
• maths/test/vector3test.cpp - Test code.

Audio Codecs

G711

An implementation of ITU-T (formerly CCITT) Recommendation G711 "Pulse Code Modulation (PCM) of Voice Frequencies"

• audio/G711.h
• audio/G711.cpp
• Documentation

G726

An implementation of ITU-T (formerly CCITT) Recommendation G726 "40, 32, 24, 16 kbit/s Adaptive Differential Pulse Code Modulation (ADPCM)"

This code optionally contains two deliberate bugs in the COMPRESS function which were added so the code passes the G726 test sequences. It seems that the standard implementation in G191 also contains these bugs.

• audio/G726.h
• audio/G726.cpp
• Documentation

Also requires source for G711

IMA ADPCM

An implementation of the IMA ADPCM audio coding algorithm.

• audio/IMA_ADPCM.h
• audio/IMA_ADPCM.cpp
• Documentation

Communications

Serial Port

Simple class for using serial ports.

• comms/serial_port.h - Abstract interface for a serial port.
• comms/windows/serial_port.cpp - Implementation for Windows.
• comms/linux/serial_port.cpp - Implementation for Linux.
• Documentation

Y-Modem

Y-Modem (and X-Modem) file transfer protocol. The receive and transmit code is separated into two classes which reduces memory size when only one of these functions is required. The code uses the Serial Port routines above.

• comms/ymodem.h
• comms/ymodem.cpp
• comms/ymodem_tx.h
• comms/ymodem_tx.cpp
• comms/ymodem_rx.h
• comms/ymodem_rx.cpp
• Documentation

Below is source for a command-line program for Y-Modem file transfer. This acts as a test program for the Y-Modem implementation and is a useful utility in its own right. It also supports receiving a 'log' after transmitting files; this can be used when sending a file to a development board and receiving instrumentation output which comes back on same port.

• comms/test/ymodem_main.cpp
• Documentation

Forth

Forth VM

ANS Forth virtual machine written in C++. This is a token threaded implementation which contains the ANS Core words plus a few extra words from other wordsets. It doesn't make use of any C library functions, and so should compile to stand-alone code suitable for embedding in other programs.

• forth/forth.h
• forth/forth.cpp
• Documentation
• forth/test/forthtest.cpp - Test code which also provides console i/o and source file inclusion by using C standard library functions.

Forth source code is also available to implement additional ANS wordsets...

• forth/core-ext.f - Implementation of missing CORE EXTENSION words.
• forth/search.f - Implementation of SEARCH-ORDER and SEARCH-ORDER EXTENSION words.
• forth/programming-tools.f - Implementation of PROGRAMMING-TOOLS words. (Doesn't include SEE.)

Test code for all implemented wordsets...

• forth/test/core.f - Test code for CORE wordset.
• forth/test/core-ext.f - Test code for CORE EXTENSION wordset.
• forth/test/search.f - Test code for SEARCH-ORDER wordset.
• forth/test/search-ext.f - Test code for SEARCH-ORDER EXTENSION wordset.

ARM Assembler and Disassembler

ARM Assembler and Disassembler written in Forth. These support all ARM architectures up to and including Version 6.

The assembler syntax closely follows standard ARM format and includes support for labels.

• forth/arm-asm.f
• forth/arm-disasm.f
• forth/test/arm-asm-disasm-test.f - Test code for assembler and disassembler.

Changes

2009-12-30

• Corrected spelling in String Formatting APIs and made some tweaks to docs.

2009-10-09

• Added test code for Utilities and Maths...
  • utils/test/stringftest.cpp
  • utils/test/bitvectortest.cpp
  • maths/test/fixtest.cpp
  • maths/test/vector3test.cpp
• Updated Forth test code so that it works non-interactively.

2009-10-02

• Code tidy-ups:
  • Removed all use of EXPORT and IMPORT macros which were used to manage symbol visability when making Windows style DLLs.
  • Made the generic ASSERT macro use AssertFailed.
  • Add test.h to contain some definitions used for writing test code.
• Made Linux version of Serial Port code use select() rather than hand rolled polling and sleeping.
• Forth virtual machine changes:
  • Fixed bug in the implemntation QUIT — the WHILE branch in XT_DO_QUIT was jumping one token to far, which would produce unpredicable results if REFILL returned false.
  • Updated the example and test class StdForthIo, to use standard Posix functions rather than Microsoft's conio.h.
  • Updated ForthVM::Accept to accept alternative keys for backspace (0x08 and 0x7F) and input end (0x0a and 0x0d).
• Changed asserts in Bit Vector to be ASSERT_DEBUG.

2007-08-18

• Added String Formatting code.
• Added Bit Vector code.

2007-05-28

• Modified Y-Modem command-line program to enable neither send nor recieve to be specified, this enables it to be abused to just capture a log from a serial port.
• Tweaked Forth virtual machine to move uncaught THROW handling into new member function ForthVM::UncaughtException. This improves the code generated by GCC.

2007-01-13

• Added option to Y-Modem command-line program to echo the captured log to STDOUT.
• Updated common.h to fix definition of offsetof to work on GGC 4, also added global placement new operator.
• Fixed GCC compilation warnings in G726 and Forth virtual machine code.

2006-11-09

• Updated Forth ARM Assembler and Disassembler to fix some ANS Forth Standard compliancey issues. (Thanks to Dmitry Yakimov for fixes and suggestions.)

2006-09-02

• Added Serial Port code.
• Added Y-Modem code.

2006-06-04

• Added options to tune implementation of Fixed-Point Maths. (See FIX_USE_64BIT_MUL and FIX_UNROLL_DIV_LOOP macros in maths/fix.cpp)
• Reorganised common.h and added a couple of useful macros.

2006-05-31

• Expanded documentation for Fixed-Point Maths code to include tips on conversion to/from fixed point numbers as well as integer arithmetic shortcuts.

2006-05-20

• Changed code to use standard typedefs, e.g. replaced uint8 with uint8_t, and made use of size_t.

2006-04-14

• Changed code licence from GPL to MIT.

2005-12-27

• Added test code for Forth programs.
• Added Programming-Tools wordlist to Forth code.
• Fixed bugs in Forth virtual machine which manifested when sizeof(CELL) was greater than sizeof(CELL*).
• Fixed a bug in the implementation of C" (forth/core-ext.f) which manifested when the size of a CHAR was not one address unit.
• Fixed a bug with the L: word in the ARM Assembler.

2005-12-26

• Added an ARM Assembler and Disassembler written in Forth.
• Documentation for C++ code now generated with Doxygen version 1.4.4.

2005-08-20

• Added an implementation of an ANS Forth virtual machine.

2005-03-02

• Made Vector3::Normal faster.

2005-03-01

• Modified Vector3::Normal so that it copes with vectors of any magnitude.
• Tidied up documentation for Vector3.

2005-02-27

• Added 3D Vectors code.

2005-02-26

• Added pseudo-random number generator function Fix::Random() to Fixed-Point Maths routines.

2005-02-18

• Updated Common headers plus other small syntactic changes so that all code compiles cleanly for Symbian OS.

2005-02-13

• Updated G726 and IMA ADPCM audio codecs to include functions for encoding and decoding multiple samples in one go. (Plus a few other minor tweaks.)

2005-02-08

• Added IMA ADPCM code.
• Added a single zip file with all code and docs.

2005-02-07

• Fixed bug in Fixed-Point Maths which caused Fix::Sqrt(0) to return 0x0000.0001.
• Updated in-source comments and produced Doxygen generated documentation.