plustek: Optic 4830P motor control
Subject:
Optic 4830P motor control
From:
Gerrit Hoetzel ####@####.####
Date:
19 Nov 2002 18:04:51 -0000
Message-Id: <20021119180020.GA1099@mc.hzhome.mine.nu>
Hi,
when I installed pt_drv the first time (sth. before 0_40_17) I was
amazed about the unexpected good implementation of the scanner; which
was much better than in this other OS.
Sometimes however the sensor hit the end of the scanning area.
Everything else worked fine.
After some time I did some updates: changed to kernel 2.4.10 and
installed pt_drv 0_40_17.
Scanning in grayscale and color worked fine. But in B/W mode the sensor
ran twice as much as specified and the resulting images became half the
size as the original.
I was able to fix this by adding the following to src/p48xx.c line 638
in function p48xxSetupScanningCondition:
if( ps->DataInf.wPhyDataType == COLOR_BW) {
ps->fHalfStepTableFlag = _TRUE;
ps->Asic96Reg.RD_MotorControl &= ps->StepMask;
}
Everything now worked fine, including sensor movement.
After some time I looked for a new challenge and tried 0_42_9 on a
2.4.19 kernel and nothing worked fine.
Sensor moved too far in graysacle, RGB and B/W. The resulting images
were half the size and colors were shifted.
The above patch worked (for B/W).
Similar changes to get graysacle and RGB to work failed.
I have an HP printer attached to the same parallel port. But it is always
turned off and I've tried everything w/o the printer attached.
I always scan at 300 dpi.
Strange that nobody else encountered these difficulties.
I am not very familiar with the code. Maybe someone could point me to
the right direction?
Actually it looks like some minor bug in what the driver thinks it gets
when moving the sensor 1 inch forward?
Thanks in advance
--
Gerrit Hoetzel
http://www.hzhome.mine.nu
