Parallel port with direct memory access capabilities

Details Parallel port with direct memory access capabilities Parallel port with direct memory access capabilities

2006-09-05

2006-09-05

Elamin, Abdelmoniem (Department: 2116)

Electrical computers and digital processing systems: support

Digital data processing system initialization or configuration

C710S022000, C710S025000, C710S059000

Reexamination Certificate

active

07103764

ABSTRACT:
The parallel or printer port in a personal computer can receive data from the memory under the control of the direct memory access (DMA) controller, releasing processor resources. The processor enables the parallel port, which then indicates to the DMA controller the desire to transfer data. A state machine in the parallel port, along with the associated circuitry, responds to the transfer of the data to the parallel port and then controls the transfer of the data to the attached device, usually a printer. The state machine causes an interrupt to the processor when the transfer is complete or on receipt of errors from the external device. The state machine also communicates with the DMA controller to repeat the transfer process until the transfer is complete or an error occurs. Various DMA channels and parallel port locations can be used. Direct transfers by the processor are blocked during DMA controller handled transfers.

REFERENCES:
patent: 4075691 (1978-02-01), Davis et al.
patent: 4079452 (1978-03-01), Larson et al.
patent: 4395756 (1983-07-01), Daniels
patent: 4431319 (1984-02-01), Karaki et al.
patent: 4463421 (1984-07-01), Laws
patent: 4467420 (1984-08-01), Murakami et al.
patent: 4639910 (1987-01-01), Toegel et al.
patent: 4730308 (1988-03-01), Friedman et al.
patent: 4755937 (1988-07-01), Glier
patent: 4802120 (1989-01-01), McCoy
patent: 4821034 (1989-04-01), Anderson et al.
patent: 4849832 (1989-07-01), Yamagata et al.
patent: 4922416 (1990-05-01), Krishnan et al.
patent: 4989113 (1991-01-01), Hull, Jr. et al.
patent: 5014237 (1991-05-01), Masters et al.
patent: 5038282 (1991-08-01), Gilbert
patent: 5090830 (1992-02-01), Kroeger et al.
patent: 5113523 (1992-05-01), Colley et al.
patent: 5150357 (1992-09-01), Hopner et al.
patent: 5255238 (1993-10-01), Ichige et al.
patent: 5539917 (1996-07-01), Jirgal
patent: 5892976 (1999-04-01), Jirgal
patent: 6138184 (2000-10-01), Jirgal
patent: 6408346 (2002-06-01), Jirgal
patent: 62208121 (1987-09-01), None
patent: 62237556 (1987-10-01), None
Abstract AU8822202, Week 6924, Derwent Publications Ltd., London, GB.
IBM PS/2 Models 90 and 95 True 486 Power at Last, PC Magazine, pp. 287-308 (Feb. 26, 1991).
Multi-I/O Card Users Manual, p. 23.
M. Morris Mano, Computer Systems Architecture, pp. 428-434 (1982).
Motorola Semiconductor Technical Data Hemos Single-Chip MicroComputer, pp. 4-1 to 4-6 (1985).
Intel Product Guide, p. 29 (1983).

Affiliated with

Also associated with

Rating

Parallel port with direct memory access capabilities does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Parallel port with direct memory access capabilities, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Parallel port with direct memory access capabilities will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3591884