Series Termination Required For Ultra Dma - Fujitsu MHS2030AT - 2.5" Notebook 30GB Drive Product Manual

Interface
i) The CRC generator polynomial is : G (X) = X16 + X12 + X5 + 1.
Note: Since no bit clock is available, the recommended approach for

5.5.6 Series termination required for Ultra DMA

Series termination resistors are required at both the host and the device for
operation in any of the Ultra DMA Modes. The following table describes
recommended values for series termination at the host and the device.
Table 5.17 Recommended series termination for Ultra DMA
Signal
DIOR-:HDMARDY-:HSTROBE
DIOW-:STOP
CS0-, CS1-
DA0, DA1, DA2
DMACK-
DD15 through DD0
DMARQ
INTRQ
IORDY:DDMARDY-:DSTROBE
RESET-
Note: Only those signals requiring termination are listed in this table. If a signal is not listed,
series termination is not required for operation in an Ultra DMA Mode. For signals also
requiring a pull-up or pull-down resistor at the host see Figure 5.8.
Figure 5.8 Ultra DMA termination with pull-up or pull-down
5-126
calculating CRC is to use a word clock derived from the bus strobe.
The combinational logic shall then be equivalent to shifting sixteen
bits serially through the generator polynomial where DD0 is shifted in
first and DD15 is shifted in last.
Host Termination
22 ohm
22 ohm
33 ohm
33 ohm
22 ohm
33 ohm
82 ohm
82 ohm
82 ohm
33 ohm
Vcc
Device Termination
82 ohm
82 ohm
82 ohm
82 ohm
82 ohm
47 ohm
22 ohm
22 ohm
33 ohm
82 ohm
C141-E171-03EN