Scanner Switches - Ricoh A284 Service Manual

BIT SWITCHES

4.2.2 SCANNER SWITCHES

Scanner Switch 00
No FUNCTION
0 Type of special original mode
0: Monotone background
1: Colored background
1-3 Not used
4 OR processing (Text mode)
0: Disabled
1: Enabled
5-7 Not used
Scanner Switch 01
No FUNCTION
0 Scan density step value
to (Text mode)
4
5-7 Not used
Scanner Switch 02
No FUNCTION
0
Binary picture processing:
to Threshold for Text mode -
7 Normal setting (center
position)
A874
COMMENTS
This setting determines the scanner parameters
used for special original mode.
0: This setting is for originals with random
background of constant density, such as seen on
banknotes (faxing banknotes is not
recommended!).
1: This setting is for originals with background of
constant density, such as those made on colored
paper.
This switch becomes effective only when system
switch 19 bit 7 is set to 1.
Do not change the settings.
1: Each pair of scan lines goes through OR
processing before transmission.
Do not change the settings.
COMMENTS
When scan density is adjusted manually away
from the Normal setting, the threshold value for
binary picture processing changes for each step
from the value specified by Scanner Switch 02, by
the amount programmed here.
For example, with the default setting (14), the
threshold value changes as follows.
+3 (Darkest) : 77 (= 91 – 14)
+2 : 91 (= 105 – 14)
+1 : 105 (= 119 – 14)
0 (Normal) : 119 (Scanner Switch 02 setting)
-1 : 133 (= 119 + 14)
-2 : 147 (= 133 + 14)
-3 (Lightest) : 161 (= 147 + 14)
The value can be between 00 and 1F(H) [=
31(D)].
For smaller steps, input a lower value.
Do not change the settings.
COMMENTS
This setting determines the threshold value for
binary picture processing in Text mode (when the
scan density setting is at the center).
The value can be between 01 and FF. For a
darker threshold, input a lower value.
Default setting: 77(H) = 119(D)
4-28 SM