Query Structure Output. Query data are always presented on the lowest-order data outputs (D7 - D0) only. The numerical offset value is the address relative to the maximum bus width supported by the device. The Query table device starting address is a 10h byte address for a byte-wide (x8) device, 10h word address for word-wide (x16) device, 10h “d-word” address for a x32 device, etc. Thus for the byte-wide (x8) device, the first 2 bytes of the Query structure, “Q” and ”R” in ASCII, appear at device addresses 10h and 11h, which is the same as the absolute byte address. These same data appear on the low byte at word addresses 10h and 11h in a word-wide (x16) device. A CFI-compliant device must output 00H data on upper bytes. Thus, an x16 device outputs ASCII “Q” in the low byte (D7-D0) and 00h in the high byte (D15-D8). The same logic extends to x32 and larger devices, such that: 1) the data are presented in the lowest byte, 2) the data are addressed in maximum-bus-width-relative addresses, and 3) the upper bytes in each data word are filled with 00h data. Thus outputs D31 - D8 of a x32 device present 00h data during Query read, starting at d-word address 10h or byte-relative address 40h. In devices that are x8/x16 capable, the x8 data is still presented in word-relative (16-bit) addresses. However, the “fill data” (00h) is not the same as driven by the upper bytes in the x16 mode. As in x16 mode, the byte address (A0 or A-1 depending on pin-out) is ignored for Query output so that the “odd byte address” (A0 or A-1 high) repeats the “even byte address” data (A0 or A-1 low). Therefore, in x8 mode using byte addressing, such devices will output the sequence “Q”, “Q”, “R”, “R”, “Y”, “Y”, and so on, beginning at byte-relative address 20h (which is equivalent to word offset 10h in x16 mode). Again, this is extensible to x32 and wider devices in that byte addresses are ignored during Query output in x8 mode such that: 1) Query data appears to repeat at each byte address within a word and, 2) the Query data starts at the byte address 10h times the number of bytes of maximum device bus-width.
