VL-bus/PCI-bus bridge

Details VL-bus/PCI-bus bridge VL-bus/PCI-bus bridge

1996-09-18

1998-08-04

Teska, Kevin J.

Boots, shoes, and leggings

364240, 3642408, 3642405, 364DIG1, G06F 1314, G06F 1342

Patent

active

057908311

ABSTRACT:
A PCI-bus is added to a VESA local bus (VL-bus) computer system using a VL-bus/PCI-bus bridge. The VL-bus/PCI-bus bridge claims a VL-bus cycle by asserting LDEV# to the VL-bus/system-bus bridge. If no other VL-bus device claims the cycle as well, then the VL-bus/PCI-bus bridge translates the cycle onto the PCI-bus and awaits a response from a PCI device. If no PCI device claims a cycle by the PCI-bus device claiming deadline, then the VL-bus/PCI-bus bridge asserts BOFF# to the host and suppresses its assertion of LDEV# when the host repeats the cycle on the VL-bus. The VL-bus/system-bus bridge therefore can translate the repetition of the cycle onto the system bus. When asserting BOFF# to the host, the VL-bus/PCI-bus bridge also asserts the VL-bus device ready signal LRDY# after assertion of BOFF# and releases LRDY# before releasing BOFF#. The VL-bus controller does not receive BOFF# necessarily, but responds to LRDY# by asserting RDYRTN# onto the VL-bus, thereby signifying to all other VL-bus devices that the VL-bus cycle has ended and permitting them to restart their state machines in anticipation of a new VL-bus cycle. The host ignores RDYRTN# while, and only while, BOFF# is asserted.

REFERENCES:
patent: 5218690 (1993-06-01), Boioli et al.
patent: 5309568 (1994-05-01), Ghosh et al.
patent: 5335326 (1994-08-01), Nguyen et al.
patent: 5379384 (1995-01-01), Solomon
patent: 5446869 (1995-08-01), Padgett et al.
patent: 5448704 (1995-09-01), Spaniol et al.
patent: 5455915 (1995-10-01), Coke
Acer Laboratories, Inc., "M1429G/M1431/M1435", Datasheet (Oct. 1993).
Acer Laboratories, Inc., "M1435 PCI-VL Bus Bridge", Preliminary Data Sheet (Sep. 20, 1993), pp.1-7, 13-14.
Acer Laboratories, Inc., "Pentium Solution of ALI", ALI Pentium Seminar (1994).
Slater, Michael, et al., "Local Buses Poised to Enter PC Mainstream -- Intel's PCI and VESA's VL-Bus Vie for Vendors' Attention", Microprocessor Report (Jul. 2, 1992), pp. 7-13.
Intel Corporation, "i486.TM. Microprocessor", Databook (Nov. 1989).
Intel Corporation, "82434LX/82434NX PCI, Cache and Memory Controller (PCMC)", Advance Information (Mar. 1994), pp. 1-30, 70-104.

Affiliated with

Also associated with

Rating

VL-bus/PCI-bus bridge does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with VL-bus/PCI-bus bridge, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and VL-bus/PCI-bus bridge will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1189061