IBM RS/6000 - Manual (Page 50)

PCI SCSI-2 Differential Fast/Wide Adapter
The adapter can burst data to devices on the SCSI bus at 20 MB/sec.
It has a single connector for attachment of external differential devices. It is a
shielded 68-conductor connector consisting of two rows of 34 female contacts.
Both 8-bit and 16-bit device attachments are supported, but intermixing 8-bit and
16-bit devices is not supported.
The maximum number of addressable IDs enabled by the adapter is 15, but due to
cabling restrictions, the actual total number of supported devices attached to the
internal and external connector may be less.
The adapter occupies one PCI bus slot, and a maximum of six adapters can be
installed in the Model E20.
The following table shows the maximum number of both internal and external
devices that can be attached to a SCSI-2 adapter together with related cables. By
“Multi-device,” we mean an external enclosure that may contain more than one
SCSI device.
Table 6. SCSI Adapter Connections on Model E20
Adapter Maximum number of devices Cables Feature Code
Feature
Code
Internal External Internal External
Single MultiDevice
Native 7 0 0 Not
required
Not
allowed
2408 4 4 0 2442 2111,
2113,
2115, 2117
2408 0 4 0 Not
allowed
2111,
2113,
2115, 2117
2408 0 0 1 Not
allowed
2111,
2113,
2115, 2117
2409 0 25 meter cable maximum Not
allowed
2112,
2114, 2116
Note: Maximum SCSI adapters: 6
2.4.2.6 Communication Adapters
The following communication adapters are supported:
Auto LANstreamer Token-Ring PCI Adapter
PCI Ethernet Adapters
ISA X.25 Adapter
ISA 4-Port Multiprotocol Communications Controller
ISA 8-Port Asynchronous Controller EIA-232
ISA 128-Port Asynchronous Controller
26 Introduction to PCI-Based RS/6000 Servers