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Got a new toy...DEC 400xP | by mr.coffee | 2002-07-23 16:05:30 |
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i might | by nimdokk | 2002-07-23 16:11:58 |
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nimdokk at? | by mr.coffee | 2002-07-23 16:23:21 |
| oooh.... |
by mr.coffee |
2002-07-23 16:28:33 |
Up to four 8x4 Intelligent Host Adapters can be installed within a host system. 8x4 host adapters connect to Central Data terminal concentrators, which offer a multiple-processor distributed architecture. This places intelligence both on the 8x4 host adapter and each remote 8-channel terminal concentrator unit. Different host adapter types can be intermixed within a host system, and the host adapters support intermixed terminal concentrator types.
Connections between the 8x4 host adapters and terminal concentrators are made through high speed RS-422 links. These host-to-concentrator connection cables can be as long as 1,000 feet (300 meters).
The 8x4AT and 8x2AT host adapters are half-length (the 8x4GT host adapter is full-length), and require a single slot in an ISA or EISA PC. The 8x2AT and 8x4AT host adapters feature 64K of dual-ported memory for data buffering and communication with the host processor (there is 128K on the 8x4GT), and they have an 80188 (80286 for the 8x4GT) processor. The host adapters send and receive data packets between the on-board processor and the attached terminal concentrators. This off-loads some of the character processing overhead from the host processor. Each terminal concentrator has a Z80-type processor and 40K of memory to handle the lower level processing of terminal I/O. In a full 32-port host adapter/terminal concentrator configuration, five microprocessors share the serial I/O workload.
The table below summarizes the host adapter types:
Central Data Host Adapter Summary
Adapter Type - Maximum Serial Ports per Adapter - Maximum Serial Ports per Host
8x2AT - 16 - 64
8x4AT - 32 - 128
8x4GT - 32 - 128
Wonder if I can find the cables.... |
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