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VHDL (I)

mauriziostefani — Tue, 15 Jul 2008 14:33:40 -0500

Overview
I do not want to make a course about VHDL as a programming language for HW (there are a lot of books better than my words 1), because courses and specifics of languages are public and everyone can find them easily on the Net. I just want to give some suggestions / recommendations by whom, starting many years ago, has had to develop an endless series of projects at different levels of complexity .

Connect A Local Device to A Remote Server

allankliu — Sun, 13 Jul 2008 22:28:26 -0500

More and more desktop applications are migrated to web based, including Office suite and instant messenger. Now we can find some web enabled devices that can connect to the remote server via regular web page. This blog presents some existing solutions and alternative solutions for such applications.

Lost or just seeing the sights ...?

froa0112 — Thu, 10 Jul 2008 17:47:00 -0500

Secure Design Using a Microcontroller III

allankliu — Wed, 09 Jul 2008 21:51:17 -0500

Crystals are key component of practical electronics devices. The product will malfunction if the crystal stops. They are heartbeat of the product. Because crystals are mechanical devices, it is sensitive to the mechanical damage. Crystals can present challenges to design engineers. However, new packaging methods and careful circuit layout can help to minimize many issues. Improved package designs, such as surface mount, incorporate lower mass and higher pin count to support the crystal body. This are excellent solutions for mechanical vibration related failures. SMT spreads mass over larger base and uses additional leads and improved lead strength. Regardless of the package style used, the body of the crystal should be mounted flush with the board.

Secure Design Using a Microcontroller (II)

allankliu — Tue, 08 Jul 2008 04:33:22 -0500

The software trap is a programming feature used to capture an abnormal program running status. The general principle is to setup a trap for software, and redirect from the code out of control to a specified address, and get back to its normal running mode. The software traps can be placed between the user codes or after the jump instructions, or be placed in the unused space by a consecutive trap codes. The most popular trap code for 80C51 is 5 byte instruction, which is:

Secure Design Using a Microcontroller (I)

allankliu — Fri, 04 Jul 2008 20:14:32 -0500

The microcontroller is widely used in many devices, which works in environment. The microcontroller has to face the challenges from EMI, voltage stability, crystal failure and much other interference. If the interferences are strong enough to disturb the operation, the system design should be secure enough to deal with these matters, one good practice is to reset and go on with previous normal operation state . However, a simple reset is not enough at all. I will demonstrate the basic principle for the system reset and state restore. Please keep in mind that the terminologies used in this article may come from different microcontrollers.

FLEX Board USB connection

Ionela — Tue, 01 Jul 2008 04:51:11 -0500

This demo shows how to set up a USB connection between the PC and the FLEX board. The aim is to control the dsPIC LED and the PIC18 LED system from the host PC. The dsPIC LED is controlled by the SPI communication with the PIC18.
The application is divided into three parts:
1. In the first part a brief description of the USB set-up is provided. The aim is to give a brief overview of the USB protocol.
2. The second part concerns the dsPIC side with the use of the SPI connection with the PIC18.
3. The third part concerns the PC side application. You can download a simple application under Windows (XP or Vista) to communicate with FLEX in order to switch on and off both LEDs of dsPIC and PIC18.

TCP/IP stack for FLEX

Ionela — Thu, 26 Jun 2008 04:42:34 -0500

This software implements a TCP/IP stack demo usable with FLEX boards. It enables communications with the board over an ethernet cable, using a variety of protocols. Here are some of the protocols included in the demo: DHCP (Dynamic Host Configuration Protocol), FTP (File Transfer Protocol), HTTP (Hypertext Transfer Protocol), SMTP (Simple Mail Transfer Protocol), SNMP (Simple Network Management Protocol), Secure NTP (Network Time Protocol), Telnet.
The demo was produced adapting the Microchip Technology Inc. TCP/IP Stack (version 4.18) and the related application notes.
This is the list of hardware components needed to use the demo:

Embedded Web Services

allankliu — Wed, 25 Jun 2008 03:27:11 -0500

The embedded internet is very common in latest electronics devices. The embedded web server used to be a hot topic since this technology can leverage common information technology infrastructure, including modem, Ethernet, PPP dial-up and web browser; there is no need to install any software on client computers. A lot of consumer electronics have already installed with embedded web servers, from router, switch, internet radio to NAS and IPTV. In the industrial field device market, ARC predicts that over the next five years, IP/Ethernet will dominate all field connections except for the final connection to the lowest level sensors and actuators. Besides to tftp and telnet, embedded web server is the most common technology used in both consumer and industrial electronics devices, especially for the classic "head-less" embedded systems, which has limited or no display at all.

FLEX: Image acquisition firmware for Video Smart Sensor

Ionela — Thu, 19 Jun 2008 04:52:34 -0500

This demo demonstrates a procedure for image acquisition from a camera equipped with serial interface on CMOS levels using FLEX.
FLEX is a platform board for embedded modular systems that exploits the potential of Microchip family’s dsPIC DSC microcontroller. It is an ideal board for developing real-time applications because the onboard dsPIC33FJ256MC710 microcontroller supports advanced real-time kernel, such as the Evidence Srl’s Erika Enterprise.