Sailor RE2100, Техническое руководство

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3 SERVICE RE2100
CHECK OF MICROPROCESSOR
Control of Strap in P02.
If the strap is connected between pin 1 and pin 2, the microprocessor will read the programme from
internal ROM. This is only used if the microprocessor U07 is mask programmed. In that case the ROM
U06 will not be mounted. If the strap is connected between pin 2 and pin 3, the microprocessor will read
the programme from U06.
Control of Strap in P03.
If the strap is connected between pin 1 and pin 2, the microprocessor will run in service programme mode.
The display will read out “SP- “. Look up the description of Service Programmes in chapter 3.10. If
the strap is connected between pin 2 and pin 3, the microprocessor will run the normal programme.
Control of the Internal Clock Frequency.
Connect a frequency counter to U07 pin 64. The frequency must be 2000 kHz +/-16.0 kHz (X-tal/4).
CHECK OF EXTERNAL ROM
If the microprocessor is strapped to external ROM, control the strap in P01. If the strap is connected
between pin 1 and pin 2, the device (ROM) in socket U06 must be a 256 Kbyte type (e.g 27C256). If the
strap is connected between pin 2 and pin 3, the device (ROM) in socket U06 must be a 128 Kbyte type
(e.g. 27C128).
CHECK OF POWER LOW CIRCUIT AND WATCH DOG CIRCUIT
Control of Power Low Circuit
Adjust the 9V external power supply to 9.0V. When the power is switched on, control that the display will
read out “Error20” (there is no connection to T2130). Press the distress key (2182), and the display will
now read out “_2182.0”. Turn the 9V power supply down slowly and control the power voltage. When the
display reads out “Error00” (the 9V power supply is too low) the power supply must be approx. 7.0V.
Control of Watch Dog Circuit.
Adjust the 9V power supply to approx. 9.0V. Connect an oscilloscope to U15 pin 6 and control that the
square wave seen has a 5.0V +/- 0.5V amplitude, that the duty cycle is 50%, and that the frequency is
one of 3 possible:
1. 15 Hz. Standard after power is switched on.
2. 20 Hz. Standard for Test Alarm mode.
3. 50 Hz. Standard for Scan Run mode.
Connect a test wire between ground and U15 pin 6. Control that the microprocessor will start a reset cycle
after every 1.6 s. (the display will flash an “Error20”. Disconnect the test wire again and control that the
microprocessor will stop the reset cycle.
CHECK OF BAUD RATE GENERATOR
Connect a frequency counter to U02 pin 9. The frequency will be a 26th part of the internal clock frequency
(normally 76.923 kHz +/- 600 Hz.), and the duty cycle is 50%.
CHECK OF TUNE/ALARM TONE GENERATOR
Press the digits 0 and 1 at same time. The equipment will now be in Quick Service mode and the display
will show “SP- “.
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