NV11 Manual Set – Section 5 16
Copyright © Innovative Technology Ltd 2012 GA963-2
5.4 ccTalk
This section should be read in conjunction with the full ccTalk specification, which can
be downloaded from the internet (www.cctalk.org).
ccTalk is a serial communications protocol in widespread use throughout the money
transaction industry. Peripherals such as coin acceptors, note validators and hoppers
found in a diverse range of automatic payment equipment use ccTalk to communicate
with the host controller.
The protocol uses an asynchronous transfer of character frames in a similar manner to
RS232. The main difference is that it uses a single two-way communication data line
for half-duplex communication rather than separate transmit and receives lines. It
operates at TTL voltages and is ‘multi-drop’ (peripherals can be connected to a
common bus and are logically separated by a device address) - each peripheral on the
ccTalk bus must have a unique address.
Each communication sequence (a command or request for information) consists of 2
message packets structured in one of the formats detailed below. The first packet will
go from the master device to the slave device and then a reply will be sent from the
slave device to the master device.
Commands can have 3 primary formats:
8 Bit Checksum – No Encryption
16 Bit CRC – No Encryption
16 Bit CRC – BNV Encryption
As it is possible to use the ccTalk protocol without encryption, suitable physical
security should be employed to protect the ccTalk bus.
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