Sunday, February 15, 2015
The Micro Stop - RS232 microcontroller schematics
RS232 controlled and RS232 powered DVM-001 voltmeter kit with PC voltage display. This circuit uses a PIC12F675 8-pin microcontroller with built-in analog to digital converter. The circuit also has an op amp and resistor divider network to achieve the 54vdc max input voltage.
RS232 serial tools
This rs232 data monitor is a thoroughly field tested and reliable software tool for serial monitoring, troubleshooting and logging rs232 communication. A laptop PC and this com port monitor give you a powerful, portable and sturdy tool to aid in designing and logging rs232 data between peripherals and hosts.
Monday, August 10, 2009
Information about computers and how to interface them to all kind of equipment. Both software and hardware help is available. - Lammert Bies
- RS-232 specs
- RS-485 information
- The serial UART
- USB interface
- Modbus interface
- Unitronics RJ11
"only the data lines and signal ground are cross connected in the null modem communication cable. All other pins have no connection. An example of such a null modem cable without handshaking can be seen in the figure below."
Monday, June 15, 2009
Providing detailed electronic design information regarding Interface, Computer, Cable, Processor and Embedded Buses. - Leroy Davis
- Buses used on Personal Computers
- Computers & Peripherals
- Logic Design
The site is geared toward Engineers who develop or design equipment. There are 3 main sections; OEM Equipment / Components listings, Computer buses, and engineering design data.
Wednesday, December 12, 2007
ET the Technology Interface
"Use of a PC Printer Port for Control and Data Acquisition by Peter H. Anderson Department of Electrical Engineering Morgan State university Abstract: A PC printer port is an inexpensive and yet powerful platform for implementing projects dealing with the control of real world peripherals...."
Use of a PC Printer Port for Control and Data Acquisition
"Building an 8-bit PC-Based Logic Analyzer by Kyle C. Quinnell Department of Engineering Technology New Mexico State University Abstract This paper presents a way of using a PC computer as a an 8-bit Logic Analyzer...."
Building an 8-bit PC-Based Logic Analyzer:
An excellent study area for both Students and Teachers in the EE Domain. The important part of practical experimentation and industrial interaction is of great value to students.
A student can also on his own have a small lab in his house and start building and programming to supplement his academic training. You can build your lab from scratch, build your own test equipment. Start Somewhere. Build something and sharpen skills.
Saturday, February 17, 2007
How to Use Your PC to Measure Temperature
Thermocouples, resistance temperature devices (RTDs), thermistors and infrared thermometers are all types of temperature sensor. Which you choose depends on factors like your expected maximum and minimum temperatures, the accuracy you need and your environmental conditions.
752-RTD: RTD Resistance Temperature Measurement, Digital I/O, Counting, Analog Output
- Measure temperature using RTDs or Pt100 sensors, and voltage signals
- With extra hardware monitor thermocouples and strain gauge bridges
- Includes the powerful yet easy-to-use Windmill software for Windows: no programming required
- Connect up to 8 USB units to one PC
Temperature Control with a PC
Based on the above the Octagon computes a sensible heating/cooling current value and transmits a corresponding analogue signal to the current control electronics in the TC-box.
The current control electronics control the current provided by a big external power supply flowing through the peltier heating elements according to the signal received from the Octagon.
This is a project that will help students learn both hardware and software aspects of a control system. Here you can test out an automation program on a PC with minimum external hardware.
When you implement in the field, the system has to be a dedicated real time uC based product on custom firmware. Systems with OS + Software combination are not known to be reliable in Process Control. But OS + Software is good for Supervisory Systems which get their data from Real Time Controllers.
So a front end controller must be Rugged, Non-PC based and Non-OS based unit. This means use something like a SBC. With a Robust and Compact (means fast) firmware.
The firmware should be Polling or Interrupt based but with both internal and external watchdog. Most important a Power supply Management that resets system properly over Brown-outs and Black-outs. Even today some Embedded Systems i have to turn off and on after power resumes.
Don't Forget, Multiple Watch Dogs and Multiple Power Management for graceful start of system !! Use one big SuperCap if you want. Else people will go back to Thermostats.