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TTFSampler - Sample sheet generator for TrueType fonts

TTFSampler is a utility that takes a list of TrueType fonts on the command line and generates a sample sheet in PDF format. The sample sheet contains several lines of text with each line demonstrating the appearance of a different font.

The latest version is v0.5.

PHP Utilities

I have written several small libraries in PHP, and most of the time I just quietly uploaded them to my FTP server and said nothing more unless someone asked. None are particularly well-documented, and they're not really intended to be used by people who can't read the source code, but they are all free software.

In order to make these libraries more accessible to busy web developers, I have created this list of short descriptions for each one.

Math: Calculating the Pearson product-moment correlation coefficient

The Pearson product-moment correlation coefficient (PMCC) is a quantity between -1.0 and 1.0 that estimates the strength of the linear relationship between two random variables.

The PMCC in its usual form is somewhat cumbersome to calculate. Using simple algebra, I have rearranged it to form an expression that should have better numerical stability and require fewer calculations.

Writing to Flash Memory on the NanoCore12C32

The NanoCore12C32 is a 24-pin DIP microcontroller module sold by Technological Arts for about $50. It is a pre-built module designed around the Motorola/Freescale MC9S12C32 microcontroller, and it features 32 KiB of on-chip non-volatile flash memory. This document aims to serve as an introduction to writing to the 9S12's on-chip flash memory.