Money Controls SCH2, Техническое руководство

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SCH2 Technical Manual TSP016.doc Issue 3.0 – January 2005
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Money Controls 2005. All rights reserved.
Page 40 of 61
Header 167: Dispense hopper coins
Transmitted data : [ sec 1 ] [ sec 2 ] [ sec 3 ] [ sec 4 ]
[ sec 5 ] [ sec 6 ] [ sec 7 ] [ sec 8 ] [ N coins ]
Received data : [ event counter ]
[ sec… ] security bytes
The ‘Dispense hopper coins’ command is protected by a sophisticated encryption
mechanism. In multi-coin payout mode, between 1 and 255 coins can be dispensed, and the
command is transmitted with a 64-bit cryptographic code. Unless the cryptographic key
matches exactly then no coins can be paid out.
If ‘N coins’ is set to zero then no coins are paid out but the message is handled normally and
the event counter is incremented.
[ event counter ]
Value of the event counter after it has been incremented.
Normal range = 1 to 255. Zero indicates a power-up or reset has occurred.
If the received data packet has a checksum error then the event counter cannot be relied
upon and this command should not be repeated to avoid over-payment of coins. The event
counter must be read with the ‘Request hopper status’ command and compared with the last
known value.
For the payout to occur as intended, the following conditions have to be met…
¾
Valid ccTalk message - no errors in format or checksum
¾ PIN number has previously ‘unlocked’ the hopper ( if the mechanism is
enabled )
¾ Cryptographic code is correct
¾
No. of coins = 1 in single coin payout mode
¾ Hopper enabled - see ‘Enable hopper’ command
¾ No ‘Absolute maximum current exceeded’ error flag
¾ No ‘Opto fraud attempt, path blocked during idle’ error flag
¾
No ‘Opto fraud attempt, short-circuit during idle’ error flag
¾ No ‘Opto fraud attempt, short-circuit during payout’ error flag
¾ No ‘Opto blocked permanently during payout’ error flag
If any of the above error flags are set ( test by using the ‘Test hopper’ command ) then
payout is blocked. These flags can be cleared with the ‘Reset device’ command.
If the payout is blocked for any of the reasons above ( apart from a low level comms error
which will result in no reply ) then a ccTalk
NAK message is returned. The event counter is
still incremented and the next encryption key generated by the hopper .
The reason for a dispense fail is deliberately not returned for security reasons.