Question about type of wave from 8051 pin 30

[Rizwanishaq]

Is it true that 8051 pin 30 give the clock of 2 MHz if the oscillator is of 12 MHz
if yes then is it square wave or sine wave

 

[IanP]

ale in 8051

It is a square wave and:

ALE is emitted at a constant rate of 1/6 of the oscillator frequency, for
external timing or clocking purposes, even when there are no accesses to external memory. However, one ALE pulse is skipped during each access to external Data Memory - 1/12.

fttp://studies.ac.upc.edu/EPSC/SED/Manuales/80C51_FAM_HARDWARE_1.pdf

Rgards,
IanP

 

[dipal_z]

what is ale in 8051

Is it true that 8051 pin 30 give the clock of 2 MHz if the oscillator is of 12 MHz
if yes then is it square wave or sine wave

square ware.

 

[ashad]

pin details of 8051

Assalam

the Pin 30 is the ALE and if you want to use the external memory it generate the pulse for demultiplexing the address and data.......

in 8051 ALE clock pulse is out ( clock input/ 6 ) but in different varients if u are not using the external memory u can shut down the ALE

like in At89S8252 ....

 

[manish12]

8051 pin

to generate sw on ALE pin tie the EA(31) to gnd.