Supply Voltage For The Cash Register; Display Malfunctions; Incorrect Images On A Character Display - ELCOM Euro-50 Service Manual

Euro-50
The description for removing malfunctions assumes that the cash register contains the software that was originally
supplied to the customer.
Prior to replacing any components on the motherboard, measuring for shorts or values of passive parts, it is necessary
to unplug the power adapter, accumulator and all cables connected to the external interfaces.

4.1. Supply voltage for the cash register

Table 4.1. List of supply voltages
Name Typical value
VRAM 3V
VDDQ 3,3V
VDD 1,8V
AVDD 3,3V
AVREF 3V
VDDQSW 3,3V
VLCD 3,9V až 4,5V
VLCD 3,3V
VH 6-8,4V
EXT5V 5V
VIN 12V

4.2.1. Incorrect images on a character display

Table 4.2. Procedure for solving incorrect imaging of a character display - cashier display
ID Test
1 Check the connection of the display to the motherboard
Check the supply voltage for the logic of the display
2
VDDQ
3 Check the supply voltage for LCD-VLCD
4 Replace the display with a functional one
5 Launch the cashier display test (102)
30
Description
Backup voltage for RTC and external RAM
Main supply voltage
Supply voltage for microcontroller core
Supply voltage for AD converter
Reference voltage for AD converter
Supply voltage for printer logic, LEDs of end of paper sensors, and platen position sensor
Supply voltage for LCD - character display
Supply voltage for the LCD - 7-segment display
Supply voltage for printer thermal head
Supply voltage for external equipment. Brought to the connector of serial port COM1
Supply voltage from the external adapter

4.2. Display malfunctions

Steps in the case of an unsuccessful test
Adjust the loose cable. If the FPC cable is damaged, the display
must be replaced.
Check C1, connect to XC2. (E50MB.pdf, list disp-fm.schdoc)
Check C2, connect to XC2. Increase the brightness of the charac-
ter display in the service menu of the cash register. (E50MB.pdf,
list disp-fm.schdoc)
Check whether a short has occurred between signals DISPDA-
TA-1, DISPCLK-1, DISPRST1-1. Check the progress of the signals
DISPDATA-1, DISPCLK-1, DISPRST1-1 to connector XC2 with an
oscilloscope.
Service manual
Elcom s. r. o.