68kMLA Classic Interface
This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.
| Click here to select a new forum. | | SCSI adapter 80-pin to 50pin | Posted by: Karadar on 2018-09-24 13:25:50
A new description will follow
| Posted by: Karadar on 2018-09-24 14:19:22
Hello forum members,
Recently I bougt a SCSI adapter 80-pin to 50pin to connect a Compaq 313809-001 drive (4,3 GB 7200RPM) as master in my Color Classic. I tried the disk and the adapter first in een external enclosure with a termination plug– no jumpers installed - and it would show up - after partitioning with Disk First Aid- without no problems. Installed OS 7.5 on the Compaq in the enclosure. Installing the Compaq as a master in the CC with the SCSI adapter – no jumpers installed - gives first a “happy mac” and a begin of a start-up but after a few seconds the start-up ends followed by a freeze and an announcement “I had to restart with extensions off”. A second try with extensions off did not give any progress. Jumper on TPR en ID 1, as suggested on the Internet somewhere, brought also no progress (“unsufficient memory”). Jumper on TPR gave: “no FPU installed”
The jumper id’s on the Compaq are:
Connector J2
1. reserved
2. reserved
3. reserved
4. parity disabled
5. write protect
6. motor start enable
7. delay mtr start
8. force single ended
Connector J6
1. 1. Addr
2. 2. Addr
3. 4. Addr
4. 8. Addr
5. Res
6. a diode symbol
The jumper id’s (#10)on the adapter are
TPR, DLY,REM, LED, SNC, SNC, DO, ID 1, ID 2, no name.
If anyone could help with this SCSI-id - VOODO? Especially why the Compaq will show up when placed in the eclosure and why not as master in the CC. I would greatly appreciate this help. Has it something to do with termination – because that is the only difference I can remark between installing as master and installing in the enclosure and if so, how can you terminate an internal drive?
Kind regards, Karadar.
| Posted by: Trash80toHP_Mini on 2018-09-24 15:30:20
Welcome aboard!
External SCSI enclosures typically take care of SCSI ID (configurable) and Termination via Resistor Networks with a switch or removable SIP resistor packs. There's your differentiation (probably) between mounting the drive internally or in the case.
You're using an SCA to 50 pin adapter? The inexpensive adapters typically have jumper blocks for setting the SCSI ID. The better ones also have provision for termination on board.
Show us pics of both sides of your adapter.
| | 1 |
|