Intermec EasyCoder 501 XP Service Manual page 97

Chapter 15 CPU Board
15.2 Circuits, cont.
96
Electronic Key Circuit (P34), cont.
Since the communication between the RISC processor and the
key circuit is comparatively slow, the content of the key circuit
is copied to DRAM at startup and used from there. At power off,
the content is read back to the key circuit, provided there is time
enough. Thus, there is a small risk that new data may be lost,
before it has been saved back to the key circuit. The original data
in the key circuit will not be damaged, if the read-back process
should fail.
Slave Processor (IC305)
The slave processor contains an A/D converter and controls the
RTC interface, and the bar code wand interface (also see chapter
15.4).
RS-232 Driver (IC304)
The RS-232 driver circuit is socket-mounted to allow replacement
if damaged.
LTS Emitter Strap (P55)
This strap decides the intensity level of the label taken sensor (LTS)
emitter (also see Chapter 10):
Jumper fi tted:
No Jumper:
LTS Potentiometer (WR51)
This potentiometer decides the sensitivity of the receiver in the
label-taken sensor (also see Chapter 10).
Ribbon End Sensor Strap (P56)
This strap decides the intensity level of the ribbon end sensor emit-
ter (also see Chapter 7.4):
Jumper fi tted:
No Jumper:
Ribbon End Potentiometer (WR52)
This potentiometer decides the sensitivity of the receiver in the
ribbon end sensor (also see Chapter 7.4).
Debug Strap (P13)
This strap is used for debugging and program development and
must always be fi tted with a jumper during normal operation.
Intermec EasyCoder 501 XP – Service Manual Ed. 4
High intensity
Low intensity
High intensity
Low intensity