ADC to PC interface transfers data in nibbles : 12/09/99 EDN-Design Ideas / The circuit in Figure 1 uses a Centronics printer port to interface an eight-channel, 8-bit ADC to a PC. The circuit cuts the cost of addressing and decoder circuitry and saves one expansion slot for interfacing. The design uses three of the subport...

LFSR provides encryption: 09/13/2001 EDN - Design Ideas /   LFSRs (linear-feedback shift registers) find extensive use in cryptography. For example, the cryptographic algorithms in the GSM (Global System for Mobile communications) mobile-phone system rely on the use of LFSRs. An LFSR comprises a register containing a sequence of bits and a feedback function. .

Manchester co decoder fits into 32 macrocell PLD: 01/06/00 EDN-Design Ideas /  Manchester encoding is common, and this scheme erases the dc-spectrum component present in an NRZ signal in baseband transmissions. An important application is in Ethernet-interface adapters, in which several kinds of media-attachment units interfac...

Microcontroller visualizes hex code: 04/27/00 EDN-Design Ideas / In C systems, information exchanges usually use the hexadecimal 1-2-4-8 format; output data also appear in this format. Reading the hex code is not a problem; several LEDs connected to the output lines can display the answer. The problem arises when you w...

Rotary encoder mates with digital potentiometer: 03/06/03  EDN-Design Ideas / In developing electronic systems, designers look for products or ideas that may benefit from the better performance, smaller size, lower cost, and improved reliability that an IC can offer. Toward that end, the digital potentiometer emerged as an alternative to its mechanical counterpart, the mechanical potentiometer...

Sequential channel selector simplifies software: 01/04/01 EDN-Design Ideas / An efficient but powerful circuit is useful for a variety of applications with limited I/O and for which you want to use one input to sequentially select a different output channel ( Figure 1 ). When the software changes the state of only one input,...

Simple phototimer controls load: 04/18/2002  EDN - Design Ideas / In industrial and home applications, the need sometimes exists for a device that, after activation by some physical effect, such as light, temperature, or sound, switches a load on for a predetermined time. The load, such as a lamp, motor, solenoid, or heater, usually derives its power from the ac line. .

Single printer port pin acts as an encoder output: 06/07/01 EDN-Design Ideas / ( Encoders and decoders are common elements in alarm, remote-control, and measurement systems. However, most of these devices require many I/O lines when under microprocessor or PC control. For example, the HT-12E encoder has eight address pins, four...

Use your printer port as a high current ammeter: 07/06/00 EDN-Design Ideas / With a few inexpensive components and INT1Ch, you can turn the printer port of your PC into a high-current ammeter....

You've got mail: 08/19/99 EDN-Design Ideas / Many e-mail programs provide a "beep" or a pop-up message box signaling the user that a new e-mail message has arrived. If the you are too far from the computer to hear the audible signal or if the monitor is turned off, then you miss the new-mail a...