Manual for SynactiX 1
Ultra ATA/66
According to the previous ATA/IDE hard drive data transfer protocol, the signaling way to
send data was in synchronous strobe mode by using the rising edge of the strobe signal.
The Ultra ATA/33 protocol doubles the burst transfer rate from 16.6MB/s to 33.3MB/s, by
using both the rising and falling edges of the strobe signal, this time Ultra ATA/66 doubles
the Ultra ATA burst transfer rate once again (from 33.3MB/s to 66.6MB/s) by reducing
setup times and increasing the strobe rate. The faster strobe rate increases EMI, which
cannot be eliminated by the standard 40-pin cable used by ATA and Ultra ATA. To eliminate
this increase in EMI, a new 40-pin, 80-conductor cable is needed. This cable adds 40
additional ground lines between each of the original 40 ground and signal lines. The
additional 40 lines help shield the signal from EMI, reduce crosstalk and improve signal
integrity.
Ultra ATA/33 introduced CRC (Cyclical Redundancy Check), a new feature of IDE that
provides data integrity and reliability. Ultra ATA/66 uses the same process. The CRC value
is calculated by both the host and the hard drive. After the host-request data is sent, the
host sends its CRC to the hard drive, and the hard drive compares it to its own CRC value.
If the hard drive reports errors to the host, then the host retries the command containing
the CRC error.
Ultra ATA/66 technology increases both performance and date integrity. However there
are basically five requirements for your system to run in Ultra ATA/66 mode:
1.
The system board must have a special Ultra ATA/66 detect circuit, such as
SynactiX 1 mainboard.
2.
The system BIOS must also support Ultra ATA/66.
3.
The operating system must be capable of DMA transfers. Win95 (OSR2) and
Win98 are capable.
4.
An Ultra ATA/66 capable, 40-pin, 80-conductor cable is required.
5.
Ultra ATA/66 compatible IDE device such as a hard drive or CD-ROM drive.
Introduction
