Crane Snack Eenter I, Руководство по устранению неполадок и ремонту

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Snack - Based Troubleshooting and Repair Guide
1670065 Page 8 of 54 September, 2002
CAUTION::
See Multi-Drop Bus (MDB) on page 14 for more information.
a. J40 Dumb Coin Mechanism Port. 24 volt unregulated dc is supplied at pins 11 and
12 for power to 24 volt coin mechanisms. Pin 6 (reset) is used to identify the presence
of a dumb coin mechanism to the merchandiser. This reset pulse is only used once on
power up for this function and is not used again unless a mechanism is changed from
dumb to Multi-Drop Bus and back to dumb again. A low at pins 1, 2, or 3 will initiate
a payout signal to the coin mechanism’s 5, 10, and 25 cent payout solenoids. All pay-
out signals are controlled at these points through the general I/O buffered IC U6. A
low at pin 4 enables the coin acceptance circuit identifying the coin inserted into the
mechanism. This data is sent by way of the switching IC U12, through buffer U13B,
to microprocessor U1 for evaluation. Data transmission takes place at pin 5 (interrupt,
low for data present), pin 7 (data received), and pin 8 (send data). Pins 9 and 10 supply
a regulated and filtered 5 volts dc for coin mechanism logic circuit operation.
b. J41 Serial Validator Port. The communication protocol accomplished at this con-
nector is much the same as that which is done at J40. A low at pin 2 enables the bill
acceptance circuit which identifies the received bill. This data is sent by way of
switching IC U12, through buffer U13B, to microprocessor U1 for evaluation. Data
transmission takes place at pin 5 (interrupt, low for data), pin 6 (data receive), and pin
5 (send data). Pins 1 and 7 supply a regulated and filtered 5 volts dc for validator logic
circuit operation.
c. J42 Pulse Validator Port. Serial data communication represents a constant stream of
information traveling in both directions (send and receive). Pulse operation is based
on a single signal being sent and processed at the microprocessor for response. No
transfer of “data” occurs and consequently no smart responses are possible. Each bill
accepted would generate this “pulse” which is acknowledged at the microprocessor
and processed. Since no data is transferred, only a one-dollar bill can be accepted,
since each one dollar bill will generate one pulse. Acknowledgment of data about any
other bill is not possible. Pins 1 and 2 provide 115-volt ac which enables voltage con-
nected through opto coupler U11 for voltage isolation purposes. This prevents high
voltage interacting with low voltage board components. While maintaining a 5-volt dc
logic level, the pulse signal is sent at pin 4 (ground) and pin 5 connected through logic
gate U9B to microprocessor U1 send leg.
NOTE:
If machine has pulse validator only, during troubleshooting, pins 4 and 5 may be
momentarily shorted together to simulate a pulse signal and establish a $1.00
credit. If credit is established then dollar bill validator is defective, if no credit is
established the main controller board is defective.
A. Interface Board
1. The snack interface (or driver) board provides the means to perform matrix operations
(see Matrix) for all tray motors, whether located on standard snack trays or trays located
within modules (Frozen, Food, or Can). It also provides voltage for the opto coupler on the
refrigeration triac board and monitors vend door and module door switches on Frozen and
Food modules.