Seagate ST31000340NS Product Manual page 40

See the bit descriptions below for words 63, 88, and 93 of the Identify Drive data.
Note.
Description (if bit is set to 1)
Bit Word 63
0 Multiword DMA mode 0 is supported.
1 Multiword DMA mode 1 is supported.
2 Multiword DMA mode 2 is supported.
8 Multiword DMA mode 0 is currently active.
9 Multiword DMA mode 1 is currently active.
10 Multiword DMA mode 2 is currently active.
Bit Word 88
0 Ultra DMA mode 0 is supported.
1 Ultra DMA mode 1 is supported.
2 Ultra DMA mode 2 is supported.
3 Ultra DMA mode 3 is supported.
4 Ultra DMA mode 4 is supported.
5 Ultra DMA mode 5 is supported.
6 Ultra DMA mode 6 is supported.
8 Ultra DMA mode 0 is currently active.
9 Ultra DMA mode 1 is currently active.
10 Ultra DMA mode 2 is currently active.
11 Ultra DMA mode 3 is currently active.
12 Ultra DMA mode 4 is currently active.
13 Ultra DMA mode 5 is currently active.
14 Ultra DMA mode 6 is currently active.
34 Barracuda ES.2 Serial ATA Product Manual, Rev. A