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party is strictly prohibited.
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Diagnostic Tariff Test (Check Sum)
With this procedure it i possible to:
• calculate the tariff check sum
• print out the tariff program (if printer is connected and powered on)
Select For Hire position.
Press
F2 and F5 at the same time.
Both displays (
3 and 5) will show in sequence the numbers
from 0 to 9.
The printer, if connected to the taximeter and powered on, will
print out all the tariff setup.
After few seconds or when the printing procedure is fi nished
the main display (
3) will show STOP and then the tariff check
sum corresponding to the binary addition of all the programmed
parameters will appear, so each tariff will have its own resulting
checksum. The secondary (
5) display will show the fi rmware
country identifi er.
The taximeter will go back in
For Hire position after few sec-
onds
To test Data Integrity, the Tariff Data is signed with a CRC16 function.
A 16 bit CRC Check Sum is therefore calculated from the Tariff Data, and saved for a future reference. The only two
sections that are out from the check sum are the unique vehicle and owner parameters, like: “k” constant and ticket
heading.
When the checksum function is activated:
a) Tariff Programming trough PC or Smart key: if the data buffer is corrupted, due to errors in data transmission,
system errors or tampering, the CRC16 Check Sum will be different from that stored for comparison.
b) At each Trip the Taximeter recalculate the Checksum of the Tariff and compares with the stored CS. reference;
and in case of data corruption it auto locks the meter showing at any tentative of start a trip the message “Error
Csum” so it can’ t work with a wrong tariff until reprogrammed.
c) It is possible to recalculate the check sum manually, IE, by Inspectors in every moment but only when the meter
is in
FOR HIRE mode, by pressing together F2 + F5, to verify that the meter is programmed with the Right Tariff.
The CRC16 Check Sum is a number between 0 and 65535, and can be displayed on the Taximeter when wished.
000000
999999 99999
00000
. . . .
48513 XIGO3
Check Sum Firmware Version
How to enter the Self-Test function
The Check Sum
SelfCheck
N
SelfCheck
N
Tariff CRC
Bios Vers
For Hire
Firmware Version and CRC
The taximeter fi rmware is identifi ed by a version name and by a CRC16 checksum. The version name is composed by
a 3 letters prefi x, indicating the fi rmware type and eventual country version, and by a 2 digits sequential number that
indicates the version for that fi rmware type, for example “FOG15”.
The CRC16 is calculated internally by the taximeter on the whole fi rmware fl ash area. If a corruption is detected, than the
taximeter is blocked. The fi rmware version can be displayed on the taximeter by pressing at the same time K2+K3+K4
when in For Hire status. Firmware name is shown in the main display, and fi rmware CRC16 is on the secondary display.
Algorithm Short Description:
The CRC 16 Check Sum calculation in the Taximeter is the (CCITT CRC16). The polynomial used is:
Hex : 0x1021 Bin : 1000000100001
Register Init is Hex : 0000 CHECK = Hex : 31C3
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