Friday, January 24, 2014

Parity bit (PSW.0)

A parity bit, or check bit, is a bit added to the end of a string of binary code that indicates whether the number of bits in the string with the value one is even or odd.

There are two variants of parity bits: even parity bit and odd parity bit. 

In case of even parity, the parity bit is set to 1 if the count of ones in a given set of bits (not including the parity bit) is odd, making the count of ones in the entire set of bits (including the parity bit) even.

When using odd parity, the parity bit is set to 1 if the count of ones in a given set of bits (not including the parity bit) is even, making the count of ones in the entire set of bits (including the parity bit) odd.

8051 Parity flag (PSW.0)
The parity flag reflects the number of 1 s in the A (accumulator) register only. If the A register contains an odd number of Is, then P = 1. Therefore, P = 0 if A has an even number of Is. 


8051 data sheet

Tuesday, January 21, 2014

RIDE 7 Raisonance microcontroller tools




Raisonance microcontroller tools - RIDE 7

http://support-raisonance.com/extranet/home/index.php

Go to the above link and create an account to download RIDE 7 for 8051.
Please register to continue using the software after 7 day evaluation period..


EdSim51 Simulator



The EdSim51 Simulator for 8051 microcontroller
http://www.edsim51.com/

µVision IDE download

The µVision IDE from Keil combines project management, make facilities, source code editing, program debugging, and complete simulation in one powerful environment.

To download the evaluation version of  µVision IDE please visit the site 
https://www.keil.com/download/product/
1) Select the link C51 : Development tools for all 8051 devices
2) Fill out the contact info. You will get a download link.
Evaluation version is limited to 32K code size ( more than enough for educational  purposes).

Alternate download links:
http://mcaf.ee/gtscl
http://tinyurl.com/vision51