Topaz Laser QNX4 Driver Specification

The Topaz Laser Driver is intended to provide command control and telemetry interfaces to the Spectra Physics Topaz Series Laser System via an RS232 connection. It will interface to standard ARP data acquisition modules including Memo, CmdCtrl, Command Servers and TMC Data Collection.

When first invoked, the driver will register with Memo and with CmdCtrl, if present, requesting that the Quit command be forwarded. It will also attempt to establish a connection with the collection program for data reporting. Failure to establish a connection with CmdCtrl or Collection need not be fatal, although the data-reporting functions will be useless without the Collection connection.

It will then attempt to establish communications with the laser system. When communications are first established, the driver will query the laser system and report the contents of the EEPROM to Memo. It will also query the status history and output status codes starting with the latest Boot.

With the initialization complete, the driver will register it's name (topaz) with the operating system, signaling other processes that the initialization was successful and advertising the command services to the command server.

At this point, the driver enters server mode where it waits in a Receive() loop, waiting for incoming requests. The driver will handle the following messages:

Command Requests from Command Server
Supported commands include setting the diode current and the diode temperature and turning the diodes on or off.
Quit message from CmdCtrl (or topaz -q)
Causes the driver to terminate gracefully
Proxy from collection
Signals the driver to request the data set from the laser system and report it to collection.
Proxy from serial port
Signals the driver to read characters from the serial port, presumably to collect a response from a data request.
The data to be report to telemetry include: Any or all of this data may be reported in telemetry. The rate at which the data is collected and/or reported is entirely determined by the TMC program.

When reading the data set, the data read from the laser system will be checked for sanity. If any characters appear to be missing or mis-formatted, the entire record will be rejected. A fixed number of rejected records may be written to the memo log in an ASCII format to facilitate debugging. A count of rejected records will be maintained and reported to Memo on termination.

Whenever the data set is collected, the status history array is compared to the previously recorded array and any new status codes are output to Memo.

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