13:25 <promach3> What does it mean by A single read or write operation for the DDR3 SDRAM effectively consists of a single 8n-bit-wide, four-clock-cycle data transfer at the internal DRAM core and eight corresponding n-bit-wide, one-half-clock-cycle data transfers at the I/O pins ?

13:28 <hell__> it means what it says. is there a specific part that you don't understand or doesn't make sense?

13:32 <hell__> basically, a single read or write operation is a burst of 8 data transfers. if your DRAM has a bus width of n bits, a single read or write operation will transfer 8n bits, or n bytes

13:34 <promach3> why four-clock-cycle data transfer ?

13:34 <promach3> and why one-half-clock-cycle data transfers ?

13:34 <hell__> and since it's DDR, both edges in a clock cycle matter, so these 8 transfers happen in 4 clock cycles, or 8 half clock cycles

13:36 <promach3> What is one-half-clock-cycle data transfers at the I/O pins ?

13:40 <hell__> `one-half-clock-cycle` is a compound adjective, which says that the 8 transfers take half a clock cycle each

13:40 <hell__> and `at the I/O pins` is in contrast with the high-level idea of a data transfer (a single read or write command)

13:43 <hell__> if you were to look at one DQ signal (one differential pair) with a scope or something, you would see that a single read or write command results in 8 bits being sent sequentially

14:01 <promach3> ok