det@nightowl.MN.ORG (Derek E. Terveer) (05/17/91)
neese@adaptx1.UUCP writes: >Your terminator scheme should be as follows: >If you have a device on the external connector of the 1542 and add a device >to the internal connector, do the following: >Remove the terminators from the 1542. Make sure the last device on the >external connector of the SCSI bus has terminators. Make sure the last >device on the internal connector of the SCSI bus also has terminators. I have a 1542a controller to which i have an (internal) wrenIV hooked up. I wish to add another one or two drives but they must be connected externally (no more room in the case (:-(). The AHA-1540A/1542A user's manual [(c) 1989] that i have for the 1542a states on page 3-2 that i must remove the terminators at locations RN3, RN4, and RN5. Unfortunately for me, my board (ANNIE II, ASSY 416006-00 rev 3e [originally 3a], BIOS 420403-00 2A @ 1988) doesn't appear to match the documentation (actually, it is probably the reverse). The only removable resistor packs (DIP) are in the upper right corner and are labled RN2 and RN4. The other resistor packs are the long skinny kind with 8 or 10 pins and look like a tiny comb. They are soldered directly to the board and are labeled RN1, RN3, RN5, and RN6. They are scattered at various locations all over the board (RN1 by J1, RN3 by J4, RN5 and RN6 by the BIOS). Are the terminators for this board really the two removable resistor DIPS RN2 and RN4? If so, why did the board change the number of packs from 3 to 2 or from 2 to 3 (depending on which came first; my documentation or my board)? One more question. The wren IV is capable of sync operation while the wren III is not. Would it help or hinder to enable the sync negotiation jumper on the 1542? I'm guessing that is should not be a problem for the wren III, right? The "OEM" manual for the wren IV doesn't mention any way of enabling the sync option on the drive except via software. If the 1542 has sync negotiation enabled via the jumper, will it be able to initiate sync operation with the wren IV or will this command have to come from the driver (in my case Esix 5.3.2-D)? Also, what kind of speed/throughput can i expect from sync vs. async operation on this drive (and/or in general)? thanks for any information and please e-mail to det@nightowl.mn.org, derek -- det@nightowl.mn.org