[. . . ] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ST9655 Family . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Product Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ST9655 Family . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Product Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ©1994 Seagate Technology, Inc. A September 1994 Seagate®, Seagate Technology® and the Seagate logo are registered trademarks of Seagate Technology, Inc. [. . . ] Figure 3 on page 14 provides mounting dimensions for the ST9655 family drives. These drives conform to the industry-standard MCC directmounting specifications and require MCC-compatible connectors in direct-mounting applications. To avoid damaging the drive: · Use M3X0. 5 metric mounting screws only. · Do not insert mounting screws more than 0. 150 inches (3. 81 mm) into the mounting holes. · Do not overtighten the screws (maximum torque: 3 inch-lb). 14 ST9655 Family Product Manual, Rev. A Dimensions are in inches (mm) 0. 747 ± 0. 007 (18. 97 ± 0. 18) 4. 010 (101. 85) max. (head/disc assembly) 0. 118 ± 0. 010 (3. 00 ± 0. 25) 0. 000 4X 3 mm × 0. 5 mm × 0. 15 in. full thread 1. 227 ± 0. 020 (2 each side) (31. 17 ± 0. 51) 4. 020 (102. 11) max (head/disc assembly to tip of pins) 1. 500 ± 0. 010 (38. 10 ± 0. 25) 1. 375 ± 0. 015 (34. 93 ± 0. 38) 0. 152 ± 0. 005 (3. 86 ± 0. 13) 0. 000 0. 155 ± 0. 020 (3. 94 ± 0. 51) 0. 000 0. 239 ± 0. 035 (6. 07 ± 0. 89) 2. 760 (70. 10) max 2. 430 ± 0. 010 (61. 72 ± 0. 25) 4X 3 mm × 0. 5 mm × 0. 15 in. full thread Pin 20 removed for keying 0. 079 (2. 00) Pin 1 0. 157 ± 0. 015 (3. 99 ± 0. 38) 0. 079 (2. 00) 1. 659 (42. 14) Figure 3. Mounting dimensions for the ST9655 family drives ST9655 Family Product Manual, Rev. A 15 2. 3 Master/slave configuration A master/slave relationship must be established between multiple drives attached to a single AT bus. You can configure a drive to become a master or slave by setting the master/slave jumpers, as described below and shown in Figure 4 on page 16. Alternatively, you can configure an ST9655 family drive as a master or slave using the cable select option. This requires a specialized daisychain cable that grounds pin 28 (CSEL) on one of its two drive connectors. If you attach the drive to the grounded CSEL connector, it becomes a master. If you attach the drive to the ungrounded CSEL connector, it becomes a slave. To use this option, the host system and both drives must support cable select. To configure an ST9655 family drive for cable select, install both master/slave jumpers. For the host to recognize the slave drive using the DASP­ signal, the slave drive must assert the DASP­ signal at power up, and the master drive must monitor DASP­ at power up. Jumper for pins A and B Removed Jumper for pins C and D Removed Configuration Drive is master; slave drive may be detected using DASP­ signal. Differentiate master and slave drives using cable select: If the drive is attached to a connector in which pin 28 is grounded, it becomes a master. If the drive is attached to a connector in which pin 28 is ungrounded, it becomes a slave. Removed Installed Installed Installed Removed Installed 2. 4 Configuring a remote LED The drive indicates activity to the host through the DASP­ line (pin 39) on the ATA interface. [. . . ] This prevents conflicts between Rest/Resume commands and other power-management commands. If either the DRQ or BSY bits are set, the host may use the DASP­ signal to determine when to initiate a Rest command. The drive asserts DASP­ when a Rest command is received and negates it upon completion of the Rest command. After the Rest command is issued, the host should wait up to 10 seconds for the drive to assert INTRQ. [. . . ]