Data rate equalisation to account for relatively different printhead widths

• US 7,121,639 B2
• Filed: 12/02/2003
• Issued: 10/17/2006
• Est. Priority Date: 12/02/2002
• Status: Active Grant

• Current Assignee: Memjet Technology Ltd. (Memjet Limited)
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Plunkett, Richard Thomas
• Primary Examiner(s): Tokar, Michael
• Assistant Examiner(s): FIDLER, SHELBY LEE
• Application Number:
  US10/727,204
• Publication Number:
  US 20040223010A1
• Time in Patent Office: 1,050 Days
• Field of Search: 347/13, 347/42, 438/21, 358/1, 358/4, 358/426.03, 400/124.11, 400/124.15
• US Class Current: 347/13
• CPC Class Codes: B41J 2/04505 aiming at correcting alignment
• CPC Class Codes: B41J 2/04508 aiming at correcting other parameters
• CPC Class Codes: B41J 2/0451 for detecting failure, e.g. clogging, malfunctioning actuator
• CPC Class Codes: B41J 2/04528 aiming at warming up the head
• CPC Class Codes: B41J 2/04541 Specific driving circuit
• CPC Class Codes: B41J 2/04543 Block driving
• CPC Class Codes: B41J 2/04563 detecting head temperature; Ink temperature
• CPC Class Codes: B41J 2/04573 Timing; Delays
• CPC Class Codes: B41J 2/04586 controlling heads of a type not covered by groups B41J2/04575 - B41J2/04585, or of an undefined type
• CPC Class Codes: B41J 2202/20 Modules
• CPC Class Codes: G06F 21/554 involving event detection and direct action
• CPC Class Codes: G06F 21/57 Certifying or maintaining trusted computer platforms, e.g. secure boots or power-downs, version controls, system software checks, secure updates or assessing vulnerabilities
• CPC Class Codes: G06F 21/575 Secure boot
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• CPC Class Codes: G06F 21/71 to assure secure computing or processing of information
• CPC Class Codes: G06F 21/73 by creating or determining hardware identification, e.g. serial numbers
• CPC Class Codes: G06F 21/74 operating in dual or compartmented mode, i.e. at least one secure mode
• CPC Class Codes: G06F 21/78 to assure secure storage of data address-based protection against unauthorised use of memory G06F12/14; record carriers for use with machines and with at least a part designed to carry digital markings G06K19/00
• CPC Class Codes: H03K 5/1252 Suppression or limitation of noise or interference specially adapted for transmission systems H04B15/00, H04L25/08
• CPC Class Codes: H04N 1/405 Halftoning, i.e. converting the picture signal of a continuous-tone original into a corresponding signal showing only two levels
• CPC Class Codes: Y10S 707/99933 : Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99939 : Privileged access
• CPC Class Codes: Y10T 29/49401 : Fluid pattern dispersing device making, e.g., ink jet

Abstract

A printer controller configured to generate dot data for supply to a printhead that includes at least first and second longitudinally extending printhead chips that are positioned adjacent each other either side of a join region such that a printing width of the printhead is wider than the length of either printhead chip, the printer controller being configured such that, in the event that the printhead chips to which dot data is being supplied are of sufficiently unequal relative length, the dot data is supplied more frequently, or at a higher rate, to the longer of the two printhead chips.

Claims

1. A printer controller configured to generate dot data for supply to a printhead that includes at least first and second longitudinally extending printhead chips that are positioned adjacent each other either side of a join region such that a printing width of the printhead is wider than the length of either printhead chip, the printer controller being configured such that, in the event that the printhead chips to which dot data is being supplied are of sufficiently unequal relative length, the dot data is supplied more frequently, or at a higher rate, to the longer of the two printhead chips.

2. A printer controller according to claim 1, configured to supply the dot data to the printhead modules such that none of the printhead modules is full and ready for printing substantially earlier than any of the other printhead modules.

3. A printer controller according to claim 1, wherein the dot data is supplied to the printhead from a memory under the control of the printhead controller.

4. A printer controller according to claim 1, including a hardware module for undertaking the task of bandwidth management.

5. A printer controller according to claim 4, wherein the hardware module is also configured to compensate for different length printheads.

6. A printer controller according to claim 1, configured to manipulate the supply of dot data to each of the printhead modules such that memory bandwidth usage is substantially constant during a printhead loading cycle.