Leica M500 N, Service Manual

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Service manual M500 N, M520, M525 Description
Doc Code 10 665 751
1-11
08/2007 Gahe
Control unit
Blockdiagram
Powering
Control units before 03/2005 had a power inlet for 230VAC ad the built-in power supply could feed the system with
+24VDC. This was required in stand systems having no own power supply like the MC1.
Since 03/2005 all stand systems have their own power supply. So the power supply was removed from control unit,
now it is supplied via the CAN bus cable with 24VDC.
Processor
An Intel 386EX Processor is used. It is clocked with 20MHz. The memory consists of 256kByte RAM, 256kByte Flash-
EPROM and 4kByte EEPROM. The
software can be updated/downloaded through the RS232 service-interface.
A watch-dog is integrated, it observes the running of the main program. Diagnosis LED’s might help with trouble
shooting, refer to
chapter 4 – fault finding / diagnosis LED’s .
Processor
CAN-
Controller
82527
Flash-
EPROM
256KByte
EEPROM
4 kByte
Watchdog
Timer
RAM
24V
5V
CAN-
Bus
J2
DC
AC
Relay
contact
Function
keys
J5
P7
RS232
J8
J3
CAN-
Bus
J6
DUART
"Gold"-
capacitor
J9
J10
RS232
5V
5V
steuerge.ds4
256kByte
2
2
Power-off
Timer
386EX CPU,
PLD Glue Logic,
Bus Transceivers
CLK2
40MHz
CAN-
Trans.
5V
J11
LCD - Graphic Controller
max 230V AC
LCD - Display
240 x 128 Dots
with VF-backlight
Service,
Download
Hand-/Footswitch 1 and 2
Relay
contact
+24V
Power supply
removed since
03/2005