Printer Stepper Motor Control
Scanner and Video Control
Vertical printer motor control lines consist of four
pins PM[3:0]/GPO[3:0] designed to control vertical
printer motor movement through external current
drivers or to serve as GPO. The vertical printer
stepper motor output is controlled using a
programmable pulse width generator. Therefore,
acceleration/deceleration and constant speed motor
control are supported. The CPU only needs to
change the timer value when the motor speed needs
to be changed. The vertical motor can run at
constant speed, increasing speed, or decreasing
speed.
T.4/T.6 Compressor/Decompressor
MH, MR, and MMR compression and
decompression are provided in hardware.
Alternating Compression and Decompression (ACD)
on a line by line basis provides support for up to
three independent compression/decompression
processes. T.4 line lengths up to 8192 pixels are
supported.
Bi-level Resolution Conversion
Six programmable control and timing signals support
common CCD and CIS scanners. The video control
function provides signals for controlling the scanner
and for processing its video output. Four
programmable control signals (START, CLK1,
CLK1n, and CLK2) provide timing related to line and
pixel timing. These are programmable with regard to
start time, relative delay and pulse width. Two video
control output signals (VIDCTL[1:0]) provide digital
control for external signal pre-processing or test
circuitry. These signals provide a per pixel period, or
per line period, timing; with programmable positive-
going and negative-going transitions for each period.
Scanner line lengths up to 4096 pixels are
supported.
Scanner Pipeline A/D Interface
An internal 8-bit Pipeline A/D converter (PADC) is
provided. The A/D reference input (Vref+) is made
available for control by external circuits. The
clamping, AGC, and Sample/Hold circuits are also
built-in. The PADC data output includes overflow
and underflow bits.
Video Processing
One independent programmable bi-level 1-D
resolution conversion block is provided to perform
expansion or reduction on the T4 decompressed
data and host image data. Image expansion can be
programmed up to 360% and reduction down to
33%. Vertical line ORing, shingling function and
horizontal shifting function for inkjet printing and the
vertical line filtered are also provided.
External Printer IF
Line-based Dark Level Correction Logic
compensates for the variations of the image output
voltage caused by DC offset. The MFC1000
supports two modes of shading correction: for
scanner data non-uniformities arising from uneven
sensor output or uneven illumination.
Correction is provided on either an 8-pixel group or
is applied separately to each pixel. Gamma
correction is also provided. Automatic Background
Correction (ABC), Dynamic Foreground Correction
(DFC), and 2-D Edge enhancement/MTF are
provided for text images. 2-D Edge en-
hancement/MTF and 2-D Error Diffusion/Dithering
are performed on halftone images. The MFC1000
includes a 16 x 16 dither table, which is
programmable and stored internally (8-bits per table
entry). The table is arranged in a matrix of up to 16
rows by up to 16 columns. The video processing
circuit also provides the mixed-mode
detection/processing and multi-level Resolution
Conversion for the scanner multi-level data. The
conversion ratio of the multi-level Resolution
Conversion is from 360% to 50%.
Bit Rotation
The External Printer Interface provides a connection
between the MFC1000 and the external printer ASIC
(inkjet or laser). The MFC1000 configures and
controls the external printer ASIC by setting registers
in it through system bus.
The interface includes AUXCLK, which can be used
as a clock base for the external print ASIC, an
interrupt (PRTIRQn), DMA, (DMARQ and
DMAACK), and system bus signals.
External Scanner IF
The interface between MFC1000 and the External
image processing ASIC is called the External
Scanner IF. It includes clock (AUXCLK), DMA
(DMAREQ0 and DMAACK0), and system bus
signals.
This block performs 90 degree data rotation on the
horizontal shifted print data in the printing swatch
buffer to support mono and color inkjet printing. It is
designed to prepare the printing data from the line-
based mono or color image data for each color plane
in the line buffer into a form ready for each fire cycle
of the inkjet printer. The ready form of data for the
fire cycle of the print engine means that data are bit-
rotated and interleaved in the bit order for each fire
cycle.
6
MD192
CONEXANT [ CONEXANT SYSTEMS, INC ]
