Toshiba 4006GAH Computer Drive User Manual


 
360050398
Toshiba Corporation Digital Media Network Company
Page 34 of 157
© 2005, Copyright TOSHIBA Corporation All Rights Reserved
10.3.4 Series resistance
Each signal has its own series resistance.
SIGNAL SERIAL RESISTANCE VALUE
-DIOR 82
-HDMARDY
HSTROBE
-DIOW 82
STOP
-CS0, -CS1 82
DA0,DA1,DA2 82
-DMACK 82
DMARQ 22
INTRQ 22
IORDY
-DDMARDY
DSTROBE
22
DD DD15 33
10.3.5 Signal Description
SIGNAL DIR. PIN DESCRIPTION
- RESET O (*1) 1 Reset signal from the host system; It shall be active low when system is
powered-up or when voltage fault is detected.
DD 15- 0 I/O 18- 3 16 bit bi- directional data bus between the host system and the drive. All 16 bits
are used for data transfer in the data register. The lower 8 bits, HD0- HD7, are
used for the other register and ECC access.
KEY N/C 20 Pin position 20 has no connection pin, clipped on the drive and plugged on the
cable in order to ensure correct orientation of the cable and to avoid wrong
insertion.
DMARQ I 21 DMA request signal is set by the drive to indicate that the DMA data transfer is
ready. The direction of the data transfer is controlled by write/read strobe signal
(HOST IOW or HOST IOR). This signal is used on a hand shake manner with -
DMACK.
- DIOW
STOP
O 23 Write strobe. The rising clocks data from the host data bus, HD0 through HD15 to
a register or data register of the drive.
Stop signal used by the host after the completion of Ultra DMA Burst.
- DIOR
-HDMARDY
HSTROBE
O 25 Read strobe. When active low, this signal enables data from a register or the data
of the drive onto the host data bus, HD0 through HD15. The rising edge of
-HOST IOR latches on the data on the bus from the drive.
This signal is for reporting the drive that the host system is ready to accept Ultra
DMA data.
Strobe. HSTROBE indicates that the host transfers ULTRA DMA data. The rising
edge and the falling edge of HSTROBE enable the drive to latch the data.
IORDY
-DDMARDY
DSTROBE
I 27 IORDY reports host that the BUS is available.
-DDMARDY is asserted to indicate that the drive is ready to receive the Ultra DMA
data.
Strobe. DSTROBE is asserted to indicate that the drive transfers Ultra DMA data.
The rising edge and falling edge of DSTROBE enable the host to latch the data.