Computer I/O adapters for programmably varying states of periphe

Details Computer I/O adapters for programmably varying states of periphe Computer I/O adapters for programmably varying states of periphe

1993-07-16

1996-04-30

Lee, Thomas C.

Boots, shoes, and leggings

395843, 395844, 3642423, 3642285, 3642383, G06F 930, G06F 1516

Patent

active

055133681

ABSTRACT:
DMA adapters which perform programmed data transfer operations in response to descriptors are programmed by information in the same descriptors (and adapter logic responsive to that information) to perform various ancillary control functions relative to addressable I/O devices that conventionally would be addressed and controlled directly by a host (higher level) system processor (e.g., the processor that prepares the descriptors). The ancillary control functions are variable programmably in number (e.g., in the disclosed embodiment, one descriptor can define 0, 1 or 2 discrete ancillary control operations) and effects produced by each operation are programmably variable (e.g., ancillary operation can be used by the adapter to alter states of addressed devices; for example, to prepare a device that has been transferring data in one direction, in a half-duplex mode, for transferring data in the opposite direction, or to switch to a full duplex mode, etc.). These functions hitherto have imposed significant processing burdens on the host processor and functional constraints on the adapters and devices; typically, constraints requiring the adapter and one or more devices to be idled for the time required by the host to condition the device(s). Accordingly, delegation of these functions to the adapter, allows them to be carried out without idling of any system elements and while the host is otherwise productively occupied. Also, such delegation creates new applicational possibilities; e.g., having an adapter linked to a communication channel react to remotely originated signals and set up operations tightly coordinated in real time to previously executed operations (for example, retransmission of data previously received with detected error).

REFERENCES:
patent: 4460971 (1984-07-01), Numata et al.
patent: 4783730 (1988-11-01), Fischer
patent: 4901232 (1990-02-01), Harrington et al.
patent: 5103446 (1992-04-01), Fischer
patent: 5179660 (1993-01-01), Devany et al.
patent: 5337410 (1994-08-01), Appel
patent: 5438665 (1995-08-01), Taniai et al.

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