What is a ring buffer and how to build it?

[louislu]

what is ring buffer...

right now i need a "chip" to convert modem clock n data to another speed...so can i use ring buffer to do it?

there will b a data and clock signal coming into this "chip" and this chip take the incoming data and clock output to somewhere else but in different clock speed...

if ring buffer can do it how to build it...thanks lot

 

[neoaspilet11]

ring buffer

Hello Louislu,

I think tou are referring to a ripple counter. Ripple counter can be used to decreased the clock frequency by multiples of two.. Ripple counter are sometimes called as ring counters. These counters come on an IC package all you have to do is connect a clock to it.

hope this help

 

[louislu]

Re: ring buffer

u means that ripple counter will only decreased the modem's clock frequency right? so how about it's data signal?when i change its clock speed then should i change the data's frequency too?currently the modem is running synchronous data...

thanks lot

 

[Kral]

Re: ring buffer

louislu,
A ring buffer is a series of registers. Upon receipt of a clock, the contents of each register is shifted to the next register. Data from the last register in the chain is transfered to the 1st register in the chain. Hence, the name "Ring Buffer"

For your application, a FIFO (First-in-first-out) memeory chip should do the job. Data from the input UART (or other receiving device) would be written to the FIFO. The transmitting UART (or other transmitting device) would read the data from the FIFO for transmission at a different clock rate. You have to be careful, though; If the input clock is faster than the output clock, the FIFO will overflow, unless there is a sufficiently long pause between bursts of transmission at the higher input rate to allow for the FIFO to "flush".
Regards,
Kral