JRC JLN-900 Installation And Instruction Manual page 188

1 Background
2 Jumper settings
2.1 Boot mode selection with JP5
2.2 Forced test mode with bottom tracking with JP4
2.3 Baud rate setting with JP3
2.4 Watchdog activation via JP21
3 Program update via WinFlash
This document gives a brief overview of JLN-900 Speed Log menu
system and use.
At reset a boot loading process starts up JLN-900 Speed Log. The log
boots from a Flash memory. With a jumper in position JP5, the log boots
into the normal operational mode. Without jumper in position JP5, the log
boot into the production test program.
When the log is running in normal operation mode and the jumper in
position JP5 is moved to position JP4, the log is forced into a test mode
with fix depth. The depth corresponds to the depth value entered in menu
T1.
This mode generates repetitive transmit patterns to facilitate oscilloscope
triggering during trouble shooting.
The 9-pin DSUB on the RECEIVER PCB can be set to two different
baud rates.
When the JP3 is ON the baud-rate is set to 4800, when OFF the baud rate
is 115200. When running e.g. SD4com on the DSUB the setting should
be 4800. The setting should be 115200 when running e.g. DrSal or
updating the software.
Watchdog is enabled via JP21. Remove jumper to disable watchdog. Set
jumper JP21 to position 1-2 to get reset pulses every 1.6 seconds. Set
jumper JP21 to default position 2-3 for normal operation.
Program update is possible from a PC running MS-windows. Set JP3 to
OFF, baud rate 115200. Connect the PC to the 9-pin DSUB and run the
program. Program update is usually not interfering with normal operation
except that changes to the menu system are not allowed via remote
operation. Always reset the RECEIVER PCB after updating the software,
by moving JP21 to position 1-2 for more than 1,6sec and then back to
position 2-3. It is also possible to reset by using the menu CPU reset in
the menu system, or power cycle the system.
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