Private notes


The serial link has the following characteristics:

a. Separate lines are used for transmitting and receiving data. For the purposes of this document, a control message is data that is received by the validator, and a status message is data that is transmitted by the validator.

b. Both transmit and receive data are framed using one start bit, eight data bits, and one stop bit.

c. The data bits are transmitted and received least significant bit first.

d. The data rate is either 600 BPS or 2400 BPS, selectable via an interface command. The data rate will default to 600 BPS following a reset or restart.

e. The electrical interface is the Motorola MC68HC705B16 microcontroller. The transmit output level is TTL/CMOS compatible. The receive input level is CMOS compatible (0.2 / 0.7 Vdd).

f. All messages start with an ASCII-format data byte, except for the query memory reply (this is binary data, and is retained for backward compatibility.

g. Some messages also have associated data bytes, which are either binary-format or ASCII-format (depending on message type and validator mode).


This file is the commands that can be sent to the validator / escrow and the expected response.

Escrow circuit diagram and validator circuit diagram files are just that.

SC5U09SV_Iss02 -

ValCal source code


Coin Validator Test and Calibration Utility


Millennium Coin Validator/Escrow Test and Calibration Specification


Coin Validator Test and Calibration Utility Assembly Specification