desert.cx

Here is the algorithm and some C source code to determine if two convex polygons intersect.  Also includes a function to determine if two line segments are intersecting. (Free for any use)

• poly_poly_intersect.c

Here is the algorithm and C source code to determine if a circle and a line segment intersect. (Free for any use)

• lseg_circ_intersect.c

Chuck's Power Koding is a document designed to help programmers fine-tune their techniques in ways they may not have thought of. Revolutionize your koding style now!

Here's a free implementation of the SHA1 hash algorithm. It is free for any use.

• sha1.h
• sha1.c
• sha1_test.c

This little piece of code calculates the 32 bit CRC of a buffer. It is free for any use.

• crc32.c

Here's a free implementation of AVL trees in C. These are free for any use.

• avltree.h
• avltree.c
• avltest.c

Here are some free linked lists for you. Doubly linked! These are free for any use.

• list.h
• list.c

This is a little program for the PIC16F84 that reads data from a magnetic card reader and outputs to RS232 at 2400bps.  It could probably be adapted easily to work on other PICs but I'll leave that as an excercise to the reader. 

• magcard-0.4.tar.gz