Memory subsystem for bitmap printer data controller

Details Memory subsystem for bitmap printer data controller Memory subsystem for bitmap printer data controller

1993-09-20

1996-04-23

Powell, Mark R.

395114, G06K 1500

Patent

active

055111521

ABSTRACT:
A DRAM memory controller for a printer having a single host CPU and a bitmap memory. The CPU initiates data transfers synchronously to a system clock for filling the bitmap memory, and a DMA controller initiates data transfers asynchronously to the system clock for transferring data from the bitmap memory to a print engine. The controller includes a first sequencer for controlling synchronous data transfers initiated by the host CPU, a second sequencer for controlling asynchronous data transfers initiated by the DMA controller, a refresh request generator for generating a refresh request signal which is asynchronous to the system clock, and a third sequencer for controlling memory refresh and for controlling arbtitration betwween the first, second, and third sequencers. Also provided is a method of transferring data between a bitmap memory and a print fifo in a printer. The method includes the steps of initiating a single data write transfer to a location in a dynamic RAM; reading a word of data from the location in the dynamic RAM to a first buffer using a first page-mode DRAM access; and writing data from a second buffer to the same location in the dynamic RAM using a second page-mode DRAM access.

REFERENCES:
patent: 4809216 (1989-02-01), Lai
patent: 4890226 (1989-12-01), Itoh
patent: 4992956 (1991-02-01), Kaku et al.
patent: 5197117 (1993-03-01), Kato et al.
patent: 5199101 (1993-03-01), Cusick et al.
patent: 5220645 (1993-06-01), Nakajima
patent: 5239621 (1993-08-01), Brown, III et al.
patent: 5253081 (1993-10-01), Shoji et al.
patent: 5299310 (1994-03-01), Motoyama
patent: 5341471 (1994-08-01), Yamazaki et al.
patent: 5347368 (1994-09-01), Mochizuki
patent: 5375204 (1994-12-01), Motoyama et al.
patent: 5377311 (1994-12-01), Carlick et al.

Affiliated with

Also associated with

Rating

Memory subsystem for bitmap printer data 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 Memory subsystem for bitmap printer data controller, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Memory subsystem for bitmap printer data controller will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2315723