Archive for the ‘Miscellaneous’ Category.

Hex/Bin/Dec Converter And Calculator — Updated

Based on some user feedback, I have updated the Hex/Bin/Dec converter and calculator I created a couple of years ago. Added features include shortcut to clear all fields and additional calculations besides bits manipulations. Continue reading ‘Hex/Bin/Dec Converter And Calculator — Updated’ »

MCP2210 Library — SPI EEPROM

So far, I have shown examples of using the open source MCP2210 library with MCP2210 GPIO, MCP23S08 and TC77 temperature sensor. In this post, I will show an example of interfacing the chip with an SPI EEPROM using the library. Continue reading ‘MCP2210 Library — SPI EEPROM’ »

MCP2210 Library — SPI Example Using MCP23S08

I made a few minor tweaks to the open source MCP2210 library during the past few days, and had also updated the documentation. In my previous post, I illustrated how to manipulate the GPIO pins using this library and today I will show you an example of communicating with a MCP23S08 8 bit IO port expander using SPI. Continue reading ‘MCP2210 Library — SPI Example Using MCP23S08’ »

Finicky MCP2210 Oscillator

Over the past couple of weeks, I had been busy playing with Microchip‘s MCP2210 USB to SPI converter. I was planning to create a Linux based API since Microchip only provided the Windows version. What I quickly found out though was that the oscillator circuit for MCP2210 was quite finicky, and it took me a while to find an alternative solution. Continue reading ‘Finicky MCP2210 Oscillator’ »

MaxiScan MS300 ODB II Reader Teardown

I bought an ODB II code reader to diagnose a check engine light problem of my car. The reader I got was an Autel MaxiScan MS300. This particular model is very popular as it is rather inexpensive, coming in at just around $20. Out of curiosity, I decided to open it up and take a look of what is inside. Continue reading ‘MaxiScan MS300 ODB II Reader Teardown’ »

Driving 8-Bit Parallel DAC Using STM32F4-Discovery GPIO

I finally got some time to play with the STM32F4-Discovery board I received last year. As for any microcontrollers, learning how to manipulate GPIO pins is always a good place to get started. Continue reading ‘Driving 8-Bit Parallel DAC Using STM32F4-Discovery GPIO’ »

Best Use of Cheap Webcams

A few of weeks ago, I wrote about a couple of cheap webcams I bought from Amazon. Since the focal lengths of those two seemingly identical webcams are different, I could not use them in stereo vision experiments as I had originally hoped. Continue reading ‘Best Use of Cheap Webcams’ »

The Dreaded “Cannot connect to ST-LINK!” Error Message

I got an STM32F4-Discovery board a while ago, but have not had much time to play with it. So the other day I decided to check out the GPIO functions to get myself familiarized with the board. Continue reading ‘The Dreaded “Cannot connect to ST-LINK!” Error Message’ »

Code For MCP4821/MCP4822

Microchip‘s MCP4821/MCP4822 is a low budget 12-bit digital-to-analog converter. MCP4821 is the single channel version whereas MCP4822 has two channels that can be latched simultaneously. Both chips have internal band gap references and can be controlled via SPI. Continue reading ‘Code For MCP4821/MCP4822’ »

Inoperative By Design

I recently bought two cheap webcams on Amazon and was planning to do some experiments with a dual webcam configuration. These cameras got pretty decent reviews and cost only a few dollars a piece, so I thought what could go wrong with these anyway? Continue reading ‘Inoperative By Design’ »

MSP-EXP430G2 I2C Issue Resolved

I was experimenting with I2C using my TI MSP-EXP430G2 Launchpad and ran into some issues. For a while, I could not get the I2C host and slave to talk. After having verified the coding and the hardware setup, my suspicion turned to the jumper which connects the red LED indicator to port pin P1.6. Continue reading ‘MSP-EXP430G2 I2C Issue Resolved’ »

SchmartBoard — First Impressions

For a lot of electronics enthusiasts and DIYers, hand-soldering SMT components can be a great challenge. And given the trend of component miniaturization, a lot of ICs no longer come with DIP packaging. Soldering such small components by hand without proper equipment (e.g. SMD hot air rework station) can be extremely difficult for beginners. The folks at SchmartBoard were kind enough to send me a few of their SMT prototyping boards to play with. So I decided to try them out to see how their proto-boards stack up with some of the alternatives on the market. Continue reading ‘SchmartBoard — First Impressions’ »

Featured Engineer on EEWeb

I was interviewed by EEWeb a few weeks ago, and the interview is featured in today’s Featured Engineer column. In that interview, I touched upon many topics, from my background to the projects I that I have been working on. Continue reading ‘Featured Engineer on EEWeb’ »

MSP430G2 DCO Frequencies

MSP430 LaunchPad (MSP-EXP430G2) is compatible with many of the TI‘s Value Line series of microcontrollers. For these MCUs, both the Master clock (MCLK) and the sub-main clock (SMCLK) can be driven directly by the internal DCO, without having to use an external crystal. This is very useful in situations where timing requirement is not so strict. In this blog posting, I will show you all the discrete frequencies that can be generated by only using the DCO. The charts included below will come in handy when you are designing your MSP430G2 based circuits. Continue reading ‘MSP430G2 DCO Frequencies’ »

A Short Guide On Motor Electrical Noise Reduction

This topic is nothing new and there are already quite a few good articles on the web on this. But I thought I would try to provide a more comprehensive view on this issue and give a few concrete examples on how to filter out the electrical noise from motors in your circuits. Continue reading ‘A Short Guide On Motor Electrical Noise Reduction’ »