G - Physics – 06 – F
Patent
G - Physics
06
F
354/233
G06F 13/32 (2006.01)
Patent
CA 1118529
ABSTRACT A data processor input/output controller which is particularly useful as a microcontroller for the transfer of data between a host processor and one or more peripheral input/output devices in a digital data processing system. This input/output (I/O) controller is a subchannel control- ler for offloading a goodly portion of the subchannel control function from the host processor. This I/O controller includes a microprocessor for assisting and supervising the controller internal operations. Also included in the controller is an automatic high-speed data bypass mechanism whereby data may be transferred from the host processor to the I/O device or vice versa without having to pass through the microprocessor and without requiring any intervention on the part of the microprocessor during such automatic transfer. Provision is made for enabling the microprocessor to perform other functions, such as the presentation of interrupts to the host processor and the servicing of addi- tional I/O commands from the host processor concurrently with the transfer of data via the automatic bypass mechanism. This capability is particularly useful where two or more I/O devices are connected to the controller. The automatic bypass mechanism is constructed to communicate with the host processor in a cycle steal mode. A look-ahead mechanism is provided for more quickly issuing the cycle steal requests to the host processor when operating in the automatic bypass mode. BC9-78-004
324854
Brown Lewis W.
Chisholm Douglas R.
Dixon Jerry D.
International Business Machines Corporation
Na
LandOfFree
Data processor input/output controller does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Data processor input/output controller, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Data processor input/output controller will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-444881