Fujitsu MHE2043AT, MHF2043AT, MHF2021AT, MHE2064AT manual Series termination required for Ultra DMA

Interface

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 5.15 Recommended series termination for Ultra DMA

Signal	Host Termination	Device Termination
DIOR-:HDMARDY-:HSTROBE	33 ohm	82 ohm
DIOW-:STOP	33 ohm	82 ohm
CS0-, CS1-	33 ohm	82 ohm
DA0, DA1, DA2	33 ohm	82 ohm
DMACK-	33 ohm	82 ohm
DD15 through DD0	33 ohm	240 ohm (100 MHz)
DMARQ	82 ohm	33 ohm
INTRQ	82 ohm	33 ohm
IORDY:DDMARDY-:DSTROBE	82 ohm	22 ohm

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 5.9.

IORDY DMARQ

Figure 5.9 Ultra DMA termination with pull-up or pull-down

Configuration of cable

For the configuration of the cable (common use of primary port and secondary port), DMACK signal should not be used in common. It is not recommended to use DIOR-, DIOW- and IORDY signal in common.

5-94 C141-E057-01EN