1-3
Getting Started
Decoder
The heart of the decoder is a micro-controller that provides the necessary intelligence for bar
code decoding, host I/O interface protocol, and general decoder maintenance.
The micro-controller contains a watchdog timer. The enabling/disabling and maintenance of
this watchdog are totally internal to the decoder; the host has no way of configuring the
watchdog.
The decoder's reset circuitry holds the micro-controller in reset after power up to allow
sufficient time for hardware initialization. This reset period is 70 msec. nominal at 5 V dc. A
reset can occur upon power up, or power supply voltage falling below 2.8 V nominal. A reset
time is generated in the CPU from an external resistor, capacitor, voltage detector, and
internal pull-up resistor.
The non-volatile memory stores the decoder capability parameters. After every reset, the
decoder checks for faults in the memory; if no faults are found, its contents are copied into
SE-923 Scan Engine
VISIBLE
LASER
DIODE
MYLAR
MOTOR
PHOTO
DIODE
MOTOR
DRIVER
ANALOG
SIGNAL
PROCESSOR
DIGITIZER
DIGITAL
SETTING
LASER
DRIVER
3
2
8
4
5
7
6
12
GND
VBATT
PWRDWN
RxD
TxD
RTS*
CTS*
TRIG*
* = Logic Low
9
BPR
11 WKUP*
DECODE
CPU
ENGINE
SCAN
ENABLE
LASER
ENABLE
DBP*
SOS*
C2
C1
C0
Содержание SE 923
Страница 1: ...SE 923 Scan Engine Integration Guide...
Страница 2: ...2 70 37052 01 Rev A February 1999 Symbol Technologies Inc One Symbol Plaza Holtsville N Y 11742 1300...
Страница 3: ...SE 923 Scan Engine Integration Guide 70 37052 01 Rev A February 1999...
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Страница 22: ...1 6 SE 923 Scan Engine Integration Guide...
Страница 29: ...2 7 Installation Figure 2 3 Exit Window Positioning CASE 1 CASE 2...
Страница 52: ...4 8 SE 923 Scan Engine Integration Guide...
Страница 135: ...5 83 Parameter Menus Prefix Suffix Values DATA FORMAT CANCEL...
Страница 138: ...5 86 SE 923 Scan Engine Integration Guide Scan Data Transmission Format PREFIX DATA SUFFIX 1 SUFFIX 2 0x07...
Страница 155: ...5 103 Parameter Menus Numeric Bar Codes cont d 4 5 6 7...
Страница 196: ...6 40 SE 923 Scan Engine Integration Guide...
Страница 232: ...Glossary 8 SE 923 Scan Engine Integration Guide...
Страница 236: ...Index 4 SE 923 Scan Engine Integration Guide...
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