Talk:Double data rate
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[edit] Rewrite needed
This page desperately needs a rewrite - I've corrected content, but don't have the time available currently to produce material up to the wikipedia standard. --Odii 11:14, August 1, 2005 (UTC)
[edit] Questions
effectively doubling the data transmission rate without having to deal with the additional problems of timing skew that increasing the number of data lines would introduce
Isn't the more-direct alternative increasing the actual clock rate? What's the reason for doubling the data rate but using the same clock? --Dtcdthingy 11:22, 28 Apr 2005 (UTC)
[edit] Another Question
Bus Size's Effect on DDR-xxx PC-xxxx Designation
The article gave an example that DDR memory clocked at 100MHz would transfer data at 200MHz (DDR-200) and would be designated PC-1600. How is the 1600 derived from the 100MHz? Is this assuming a 16-bit word size?
[edit] Addressing rate?
So the data is sent on both rising and falling edges. How about the addresses? Are they accepted at the same double (two-edge) rate, or is only one address accepted and two bits (or words) of data accessed from, say, successive memory locations for each address accepted? -R. S. Shaw 06:42, 29 October 2005 (UTC)
- This article discusses double data rate exclusively. As far as I understand, the design of DDR SDRAM memory technology relies on caching. Requested data is returned in a series (burst) of something like 4 or 8 transfers, some time after the request. The difference between SDR and DDR is that this burst is sent twice as fast, one transfer per clock tick, instead of one transfer per two clock ticks (SDR). Issuing requests is much slower anyway. I am basically restating this. Conf 16:24, 31 October 2005 (UTC)
