By whygee on Friday 13 November 2009, 21:54 - Project
I have been very busy since august, unfortunately not with YASEP but I keep an eye on this project. Even though I can't dedicate days and weeks to this, I try to gather things here and there when they appear, like electronic parts, ideas, and ways to implement them.
For example I've been thinking about how to display informations with a simple FPGA kit. I already have a nice collection of alphanumeric LCD modules that is expanding, so they are a good and cheap output peripheral.
From there, at least three things follow :
- The modules I own have different resolutions : from 1x8char to 4x20 but there is no electronic means to distinguish them from the others. So I recently imagined a method, discussed a bit about it on USENET and decided that it was worth implementing it. I am writing a RFC about this now.
- I'm going to add a set of Special Registers that support the parallel interface to a LCD module in nibble mode. This is going to provide automatic strobes, and ease application software development. This unit will also support readback of LCD resolution, supporting the protocol defined in 1. Contrast voltage is controlled by a simple PWM/PD circuit instead of a trimpot.
The LCD RFC was translated in French and published as an article
"Détection de la résolution des modules LCD alphanumériques" in OS#4 (2011.10)