Mercurial > hg > index.cgi
view docs/manual/x41.html @ 434:052c5f335a92
Fix bug in like terms collection in expression simplification
Like term collection would lose the actual "variable" part of the term if
the second term collected happened to have no coefficient. This would cause
the expression to take the value of the calculated coefficient which is
obviously wrong.
Thanks to hider <stego@satx.rr.com> for reporting the bug and providing a
proper test case.
Observation: this bug has been present since the first pre-release of
lwtools 3.0 when the algebraic expression system was introduced. Apparently
people tend not to create expressions that trigger the like terms handler.
The specific conditions require the symbol to be undefined and the second
operand to the addition has to have no coefficient so it's likely a fairly
rare scenario. Still, it is somewhat surprising that nobody tripped on it
before now.
author | William Astle <lost@l-w.ca> |
---|---|
date | Mon, 23 Jan 2017 22:58:36 -0700 |
parents | b30091890d62 |
children |
line wrap: on
line source
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >Intel Hex</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REL="HOME" TITLE="LW Tool Chain" HREF="index.html"><LINK REL="UP" TITLE="Output Formats" HREF="c21.html"><LINK REL="PREVIOUS" TITLE="Motorola S-Record" HREF="x36.html"><LINK REL="NEXT" TITLE="OS9 Modules" HREF="x46.html"></HEAD ><BODY CLASS="SECTION" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >LW Tool Chain</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="x36.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" >Chapter 2. Output Formats</TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="x46.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECTION" ><H1 CLASS="SECTION" ><A NAME="AEN41" >2.5. Intel Hex</A ></H1 ><P >This ASCII format consists of a series of CR+LF terminated "records" of ASCII text. Each record has the following structure: a start-of-record character ":", a two-digit ASCII hex byte count, a four-digit ASCII hex address, a two- digit ASCII hex record type, an optional sequence of two-digit ASCII hex data values, and a two-digit ASCII hex checksum. The LW tool chain issues only 00, and 01 Intel Hex record types. Data records are limited to maximum of 16 data bytes in length, and paragraph alignment of addresses is favored. The address sequence of the Intel hex records directly follows that of the source file; multiple ORG directives in the source code may result in out-of-sequence addresses in the Intel Hex output. </P ><P >Intel Hex format is the other standard ASCII format accepted by most memory device programming equipment, it and the Motorola S-Record format are used for similar purposes.</P ><P >LWASM can output this format since version 4.10.</P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="x36.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="x46.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Motorola S-Record</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="c21.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >OS9 Modules</TD ></TR ></TABLE ></DIV ></BODY ></HTML >