Arduino: MCP23008 Library

Introduction

 

MCP23008 Image

Ever needed a few extra I/O points or need to dedicate some I/O to a peripheral like an LCD or 7 segment LED?  Try the MCP23008.  The MCP23008 is an 8-bit general purpose I/O expansion chip controlled via a I2C interface.  Each of the 8 I/O point can be configured as inputs or outputs.  Inputs can be configured to use weak pull-up resistors or trigger an interrupt on change of state based on how the MCP23008 registers are setup.  The following details an Arduino driver for the MCP23008.  A simple test circuit and example program demonstrate the use of the driver.

 

Continue reading »

Oasis TOFD-5465GGH-B 4 Digit LED with PT6961 Controller

 

Introduction

The TOFD-5465GGH-B is a 4 digit 7 segment display with a PT6961 LED driver embedded on the back.  I found these on Ebay for 10 for $10 plus shipping.  Ended up being about $1.30 each.  The PT6961 is an LED driver with a SPI interface which means you can talk to it with any microcontroller (PIC, STAMP, Arduino, etc.)  I used both a PIC 18F458 & Arduino Uno to communicate with it.  Very little information was available on these displays and I owe a thanks to some members of the http://forum.43oh.com forum for pointing me in the right direction.  Below are the details regarding the implementation with an Arduino Uno controller.

 

Continue reading »

MPASM Macro : cfLES (Compare File Less Than File)

 

 

Introduction

Compares 2 file registers and determines if file 1 is less than file 2. If less than then jump to the passed address.

 

 

Continue reading »

MPASM Macro : ckGRT (Compare File Greater Than Constant)

 

 

Introduction

Compares a file register to a constant and determines if the file is greater than a constant. If greater than then jump to the passed address.

 

Continue reading »

MPASM Macro : cfGRT (Compare File Greater Than File)

 

Introduction

Compares 2 file registers and determines if file 1 is greater than file 2. If greater than then jump to the passed address.

 

 

Continue reading »

MPASM Macro : ckEQU (Compare File / Constant Equal)

 

 

Introduction

Compares a file registers to a constant value and determine if equal. If equal then jump to the passed address.

 

 

Continue reading »

MPASM Macro : cfEQU (Compare Files Equal)

 

 

Introduction

Compares 2 file registers and determine if equal.  If equal then jump to the passed address.

 

Continue reading »

HowTo – Install Usermin on Ubuntu 10.04 LTS

Introduction

Usermin is a web-based interface for webmail, password changing, mail filters, fetchmail and much more. It is designed for use by regular non-root users on a Unix system, and limits them to tasks that they would be able to perform if logged in via SSH or at the console. You can visit http://www.webmin.com/usermin.html to view the documentation and modules avaliable for usermin. The information below is based on a condensed version of a post shown in the sources and modified to install usermin.

Continue reading »

HowTo – Install Webmin on Ubuntu 10.04 LTS


Introduction

Webmin is a web-based interface for system administration for Unix. Using any browser that supports tables and forms (and Java for the File Manager module), you can setup user accounts, Apache, DNS, file sharing and so on.  You can visit www.webmin.com to view the documentation and modules avaliable for webmin.  The information below is based on a condensed version of a post shown in the sources.

Continue reading »