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C005383_10 CR80XX Integration Guide
4.6 – Electrical Control Signals (CR8011 and CR8012 only)
The CR8000 is equipped with inputs and outputs that allow the user to
control the reader and get certain status information via hardware signals. A
brief description of each signal is given in this Section. For additional details
on the interaction and timing of these signals, refer to the Timing Diagrams
and Tables in the Sections that follow. To get more information on register
functions, refer to the Interface Configuration Document (ICD), available on
the Code website (www.codecorp.com).
Pin 8 - Power Down (output):
The PwrDwn line is used to indicate the
operational state of the reader. PwrDwn will be asserted HIGH when the
CR8000 has switched to the sleep state. PwrDwn will transition back to the
LOW state when the CR8000 is not in the sleep state. The different power
modes are described in more detail in the Section 4.7.
Pin 9 – Beeper (output):
The nBeeper line is used to indicate a successful
decode, completion of the boot process, errors, and certain other conditions
or events. nBeeper can be configured to transition to a LOW state for a
specified length of time or to output a series of pulses of a specified duration
on a successful decode or on certain error conditions. The duration of
this signal can be set with register 0x59. Default behavior for this signal is
one “beep” for a good decode, two “beeps” for a successful configuration
barcode read, and four beeps if a configuration was not applied successfully.
Pin 10 - Good Read (output):
The nGoodRead line is used to indicate
a successful decode. Upon the completion of a successful scan and
decode, the nGoodRead line will be asserted LOW. The length of
nGoodRead assertion can be set with register 0x1EA.
Pin 11 – Wakeup (input):
The nWakeUp line is used to change the state
of the reader from Sleep to Idle. Once the CR8000 has entered the sleep
state, it may be awakened by asserting nWakeUp with a LOW pulse. Note
that nWakeUp must be HIGH when the CR8000 enters the sleep state in
order for nWakeUp to awaken the CR8000 on assertion. Also note that when
the sleep state is not being used, this pin should be left open, not tied low.
Please note that the Sleep state is only valid for CR8012.
Pin 12 – Trigger (input):
The nTrigger line is used to activate the reader.
To activate the CR8000, pull the nTrigger line LOW. This is normally used to
cause the reader to scan for a barcode.
Note: All output signals except USB D- and USB D+ are connected to
open drain buffers with a pull-up of 100 Kilo-ohm to
V
in
and a maximum
current capability of 50 mA. All input signals except USB D- and USB D+
are connected to a pull-up to
V
in
and to a buffer with a 50 mA maximum
current capability.
Note: When
V
in
is initially supplied, PwrDwn and the other outputs will
be LOW for a few milliseconds until the voltages on the board come up.
They will then transition to default HIGH due to pull-ups until the unit
is up and running. These signals should be ignored until the unit is fully
functioning. See startup timing diagram below for details.
4.7 – Power Modes (CR8011 and CR8012 only)
Boot Mode:
The CR8000 enters boot mode upon application of
V
in
. The
PwrDwn
pin will be HIGH (after power on delay) until the main app starts.
Active Mode:
In Active Mode the unit is capturing images and initiating the
decode process and/or storing images. The unit transitions to Active Mode
from Idle Mode when a trigger event is received.
Idle Mode:
In Idle Mode the unit is not actively capturing images. The
processor is fully functioning and communication can take place, upgrades
can be performed, and scripts can be run. Idle Mode is entered from Boot
Mode after power on, from Active Mode after a register defined timeout in
which there are no trigger events, and from Sleep Mode on receipt of a wake
up.
Sleep Mode (CR8012 only):
The imager, illumination, and most of the
processor is powered down. The CPU wake up circuitry, the memory, and
the input/output buffers are powered. The unit enters the sleep state after
a register defined timeout of inactivity, which is defined in register 0x9F. On
receipt of a wake up on the
nWakeUp
pin, the processor restores the run
environment and enters Idle Mode.
