View Full Version : digital funda

07-04-2005, 05:15 PM
wht do u mean by strobe is it equivalent to enable or something else
also tell wht is meant by chip inhibit
i read these at http://www.machinegrid.com/content/view/30/1/ms in the parallel port tutorial .

07-04-2005, 07:36 PM
this is the correct link

"Chip Inhibit" means..you can enable or disable the chip..just as "Chip select"

For an L293D,it means it can shut off that particular channel

i couldnt find the word "Strobe" on the page though..

07-05-2005, 01:24 PM
strobe i had read on anither link whxch couldn't be cpd but that's fine
actually i rad strobe against an ic pin while reading datasheet of some ic whch i don;t remember
once i get the link i'll post it
but in case u cld tell directly u cld save me some pain

07-05-2005, 09:09 PM
As far as my knowledge goes strobe pins are used for same thing as enable...They both jus switch the IC on or off ..

For some reason i noticed in the few ICs ive used strobe activates an IC when it is low(ie logic 0) while enable does it at logic 1..

Perhaps this is not general case but it could jus be tht strobe prevents noise triggering the IC... :idea:

07-07-2005, 02:00 PM
Synchronous serial transmission requires that the sender and receiver share a clock with one another, or that the sender provide a strobe or other timing signal so that the receiver knows when to “read” the next bit of the data. In most forms of serial Synchronous communication, if there is no data available at a given instant to transmit, a fill character must be sent instead so that data is always being transmitted. Synchronous communication is usually more efficient because only data bits are transmitted between sender and receiver, and synchronous communication can be more costly if extra wiring and circuits are required to share a clock signal between the sender and receiver.

A form of Synchronous transmission is used with printers and fixed disk devices in that the data is sent on one set of wires while a clock or strobe is sent on a different wire. Printers and fixed disk devices are not normally serial devices because most fixed disk interface standards send an entire word of data for each clock or strobe signal by using a separate wire for each bit of the word. In the PC industry, these are known as Parallel devices.

The standard serial communications hardware in the PC does not support Synchronous operations. This mode is described here for comparison purposes only.

this is where i read "strobe"

03-12-2006, 10:31 AM
mostly chip select is just a enable of tristate buffer

see the diagram of a RAM
In uP all data lines are connected to data lines of many chips. So if chip select is not thr the data of two chips will be on the line and wrong data will be received. If 1 and 0 comes on the line, it will become 0 bcz logic high current is around 2mA while of logic 0 around 24mA(see ibm definition for parallel port).

Strobe is not chip enable. It can act like the control signal for a latch or ram