From 0db489324b44568fc4fdd9d194ce6d17203fae88 Mon Sep 17 00:00:00 2001 From: Karl Berry Date: Tue, 14 Oct 2014 22:25:31 +0000 Subject: avremu (14oct14) git-svn-id: svn://tug.org/texlive/trunk@35373 c570f23f-e606-0410-a88d-b1316a301751 --- Master/texmf-dist/doc/latex/avremu/README | 75 ++++++++++++++++++++++++++ Master/texmf-dist/doc/latex/avremu/avremu.pdf | Bin 0 -> 146364 bytes 2 files changed, 75 insertions(+) create mode 100644 Master/texmf-dist/doc/latex/avremu/README create mode 100644 Master/texmf-dist/doc/latex/avremu/avremu.pdf (limited to 'Master/texmf-dist/doc/latex/avremu') diff --git a/Master/texmf-dist/doc/latex/avremu/README b/Master/texmf-dist/doc/latex/avremu/README new file mode 100644 index 00000000000..7fe8622e2ee --- /dev/null +++ b/Master/texmf-dist/doc/latex/avremu/README @@ -0,0 +1,75 @@ +avremu: An AVR Emulator written in pure LaTeX +====================================================== + +LaTeX is known as a typesetting system. But the underlying TeX system +is a powerful macro processor. In fact, TeX is a Turing-complete +programming language. TeX can compute anything, that is +computable. Computeability is a concept from theoretical computer +science. After visiting a theoretical CS course, you will know that +there are things that cannot be solved by a machine. Never. Look out +for the halting problem. So, Turing-complete does not say "It's a +proper programming language", but more "someone can write a proper +interpreter for any programming language in it, theoretically". + +So back to TeX. To be honest, TeX is a horrible language to code +in. After writing my master thesis in LaTex, after crafting every +graphic within with TiKz[1] and pgfplots[2], and after writing my +first LaTeX package[3], I can honestly say: TeX is the Quasimodo of +all widely used programming languages. If you can avoid it, avoid it. +But if you are forced to use it, you can abstract from TeX, since it +is a "proper" programming language. + +Let's say we want to program our document in C on Top of Tex. Then +there would be the need to interpret the C semantic. Basically we +would have to write a compiler for C in TeX. Not a very promising +future, if you start this. But, we can use a normal C compiler to +compile the C code to some simple platform. Like AVR[4]. Since I have +other things to do than writing an AVR Emulator in TeX, here it is! + +The newest source can be found at https://gitlab.brokenpipe.de/stettberger/avremu + +The package is licensed under LPPL 1.3 + +You are writing an CPU emulator in TeX, the TYPESETTING system? +--------------------------------------------------------------- + +Yep. + +What Microcontroller is emulated? +--------------------------------- + +I aimed for an ATmega8. The AVR platform is an 8 Bit Processor with 16 +Bit memory addresses. The hardware version is shipped with 1 KByte of +RAM and 8 Kbyte Flash memory, but of course, the emulated processor +can handle more memory. + +Are you insane? +--------------- + +Not that anybody knows of. + +Are all OP codes implemented? +----------------------------- + +Unfortunately not. I'm still missing 5 opcodes (MULS, MULSU, FMUL, +FMULS, FMULSU), but until now I did not encounter a C file, the +AVR-GCC emits these opcodes. The fractional multiply opcodes are also +somewhat arcane. + +Is it fast? +----------- + +Ok, you are asking me, whether a CPU simulator written in TeX, that +simulates an 8-Bit microcontroller is fast? Propably not. On my +notebook I could achieve 2.5 KHz, so this is a factor 10000 slower +than the actual hardware with the highest supported clock rate. + +----- + +[1] http://www.ctan.org/pkg/pgf + +[2] http://pgfplots.sourceforge.net/ + +[3] http://www.ctan.org/pkg/dataref + +[4] http://en.wikipedia.org/wiki/Atmel_AVR diff --git a/Master/texmf-dist/doc/latex/avremu/avremu.pdf b/Master/texmf-dist/doc/latex/avremu/avremu.pdf new file mode 100644 index 00000000000..3b10ee33a71 Binary files /dev/null and b/Master/texmf-dist/doc/latex/avremu/avremu.pdf differ -- cgit v1.2.3