Blog Archives
Posted on 10 Mar 2008
This robot control by PIC16F818 which has a lot of features that work well in this situation. As you can see from the Schematic and Source Listing, position pulses for the 2 servos are generated dirctly from the PIC. Also, the room light level, battery condition, and servo power draw (indicating mechanical loading) can be measured with the internal ADC.[more]
Posted on 10 Mar 2008
This article shows you how to build a digital thermometer from the beginning to the end, using a thermistor and a 8051 microcontroller.Being based on tutorial about Analog to Digital conversion on this website , it is very easy to understand the functioning of the device, and you can build it with any microcontroller even if it doesn’t have a builtin ADC.This digital thermometer built with the AT89S52 microcontroller.[more]
Posted on 26 Feb 2008
This project is for detecting human ECG (Electrocardiogram, or EKG). A tiny amplifier is embedded (<1mA). The on-chip Timer, ADC and DMA (double buffering) are used for getting ECG data. An IIR filter and hardware LCD scrolling are used for ECG rendering. User can simply touch the Primer by 2 hands, his/her ECG trace is scrolling alive on the LCD screen. The instant heart rate is displayed with beep sound and LED flashing. The device also delivers and displays the ECG on a PC through the USB cable.[more]
Posted on 13 Feb 2008
The module uses an inexpensive 8 bit Temperature Sensor the TMP37 from Analog Devices.Since the data was analog and the PIC16f84 does not have an analog input,an external ADC had to be used.Texas Instruments’ TLC549 was chosen for this.The advantage of this ADC was that it could communicate with the microcontroller serially.You may also use similar ADCs from Maxim-IC.The LCD is a normal 16×2 display which uses the Hitachi Controller HD44780.[more]
Posted on 13 Feb 2008
This project devised by two Cornell students in 2003,they wrote: For this endeavour, we first built an input stage that will amplify the input signal, as well as bias it to 2.5V (since the ADC can only sample positive signals). The ADC (MAX1111) is controlled by the microprocessor (Mega 32) using the SPI interface which was much easier than manually configuring a port to interface with the ADC(believe me, we tried that). We set the Mega 32 to sample the input at about 12 KHz which is fast enough to meet the Nyquist requirement for analog to digital sampling. The digital effects were done using by manipulating the input (which will be discussed in the Design page) and the output is passed to a R-2R DAC to a output amplifier stage and finally, to the speaker.[more]
