User guide

203 Series Industrial Grade 2.5" FlashDrive Product Manual v2.0Cactus Technologies

Bit 7 This bit is unknown.

Implementation Note:

Conicts may occur on the host data bus when this bit is provided by a Floppy

Disk Controller operating at the same addresses as the SSD. Following are some

possible solutions to this problem:

1. Locate the SSD at a non-conicting address (i.e., Secondary address (377) when a

Floppy Disk Controller is located at the Primary addresses).

2. Do not install a Floppy and a SSD in the system at the same time.

3. Implement a socket adapter that can be programmed to (conditionally) tri-state D7

of I/0 address 3F7/377 when a SSD product is installed and conversely to tri-state D6-D0

of I/O address 3F7/377 when a oppy controller is installed.

4. Do not use the SSD’s Drive Address register. This may be accomplished by either

a) If possible, program the host adapter to enable only I/O addresses 1F0-1F7, 3F6 (or

170-177, 176) to the SSD or b) if provided use an additional Primary/Secondary

conguration in the SSD that does not respond to accesses to I/O locations 3F7 and 377.

With either of these implementations, the host software must not attempt to use

information in the Drive Address Register.

Bit 6 (-WTG) This bit is 0 when a write operation is in progress, otherwise, it is 1.

Bit 5 (-HS3) This bit is the negation of bit 3 in the Drive/Head register.

Bit 4 (-HS2) This bit is the negation of bit 2 in the Drive/Head register.

Bit 3 (-HS1) This bit is the negation of bit 1 in the Drive/Head register.

Bit 2 (-HS0) This bit is the negation of bit 0 in the Drive/Head register.

Bit 1 (-nDS1) This bit is 0 when drive 1 is active and selected.

Bit 0 (-nDS0) This bit is 0 when the drive 0 is active and selected.