Hardware Description

Both also have 2k bytes of battery–backed static RAM (on word boundaries), a 4k x 8–bit Node Adress EPROM, two front panel mounted HEX coded switches for the CAMAC Crate Address (0–FF Hex = 0–255 decimal), a standard CAMAC Port with Memory Mapped Access, a serial port to be used mainly for test purposes, and a multiple counter/timer system to support the software real–time clock and message/task timing. An 8–bit switch port is used to set the LSAP (Link Service Access Point) address; two addresses are used; one for multicasts issued by the host and another (at switch setting plus one) for muliticasts by the Ethernet Crate Controller. There are 11 LEDs fitted on the front panel, the details are as follows:–

Firmware Description

The standard firmware supplied with the 1365 is loaded into on–board EPROMs. The major functions provided by the firmware are:–

• Support for the SONIC/LANCE Ethernet chip set.
• Driving the Controller’s internal CAMAC interface.
• Driving the Logical Link Control (LLC1 and LLC3) and UDP protocols.
• Driving the HYTEC specified CAMAC Command protocols.
• Servicing and support for CAMAC Interrupts.
• Support for Block Mode and List Mode commands. The controller is able to keep command lists resident in its RAM. These command lists may be selected and re–executed via a single short Ethernet command.
• Timer support. This includes controller timekeeping, network time protocol support and data time stamping support.
• Maintenance of booking tables. Booking tables for CAMAC station booking (booked to a single process in a multi–processing host). Also LAM booking. LAMs can be booked to a single process in a multi–processing host. Auto booking of CAMAC stations is supported.
• Security features support. Security tables in battery–backed RAM control which hosts may access this controller. ”Promiscuous” modes are supported. ie; unrestricted access from any host.
• Front–panel terminal handling. This allows a standard RS232 terminal to be connected to the controller to modify the security tables and examine the controllers statistics tables.
• Statistics gathering support. The firmware will gather statistics on Ethernet messages, failures, errors, recoveries etc., as well as CAMAC statistics such as number of LAMs, double–booking attempts, security violations and dataway timeouts.

These features combine to provide the controller with comprehensive CAMAC functionality. This includes:–

• Single–action CAMAC Commands.
• Block Mode CAMAC commands including address scan modes, LAM synchronised modes, controller synchronised modes and all Q modes.
• List Mode CAMAC Commands. Command lists may be loaded and repeatedly executed. Multiple lists are supported.
• Full Q, X, and Timeout Error Handling (by message to host).
• Normal CAMAC controls of Z, Clear, Inhibit, etc.
• Full CAMAC LAM support. Host processes are notified when booked LAMs occur.
• User defined controller commands may be down–loaded from a host and then executed (this permits applications to set up extra controller capability if needed).

Network Time Protocol

To achieve time synchronisation between multiple 1365 crate controllers and multiple hosts, a Network Time Protocol (NTP) is defined.

The protocol continually monitors and adjusts the clock times in the 1365, compensating for transmission delays, this minimises any time errors. It also ensures that the data acquisition time stamping carried out by the multiple 1365 is correct to within the error margins of the protocol. This is stated, to the first order, as equal to the transit delay being experienced on the network.

Down-Loaded Routines

The firmware allows user written routines to be down–loaded and executed on request, whilst still retaining all the normal functionality of the firmware. These user written routines can be written in C, and are able to call into existing routines in the firmware for CAMAC access, buffer allocation, message transmission and security/booking table checks. This powerful feature allows custom front end processing to be easily implemented for such applications as data reduction, data compression, data scanning and custom algorithm execution.

Host Software Support

Host control of the 1365 is achieved by HYTEC specific CAMAC command and control messages delivered to the controller using Logical Control type 1 and 3 protocols (LLC1, LLC3). Users who prefer to implement their own host support can do so using the protocol definition documents available from HYTEC on request.

Host support for DEC VAX and AXP systems is available from HYTEC. This includes device drivers, protocol handlers and a system process to manage user process requests and provide the configuration and time protocol support. Each VAX or AXP host wishing to communicate with an Ethernet Crate Controller must be running this software.

Host support in the UNIX environment is available and uses the User Datagram Protocols (UDP) a member of the Internet Protocol (IP) suite. UNIX systems that support UDP/IP can access the ECC1365 with similar functionality to the VAX and AXP host systems.

High level language support is provided through a library of subroutines that include the standard ESONE/DOE subroutines with extra routines to support the extra functionality of the controller. A system manager tool is provided to display the known configuration and individual controller statistics on a host terminal. These ESONE/DOE routines are available from VAX, AXP and UNIX hosts.

Extensive use of the VAX/VMS message utility has been made for error reporting and system information messages.

Security Features

The 1365 controller maintains a table containing the Ethernet address of host systems which are allowed to access it. The use of this table is enabled by a switch on the 1365 printed circuit board. For each addess, a mask defines which CAMAC stations the host may access and a set of capabilities defining which crate controller–wide operations the host may perform. This table is kept in battery–backed RAM. The table is either down–line loaded by suitably privileged hosts or by a terminal connected to the RS232 port on the 1365.

Power Fail

A simple circuit has been included to monitor all the CAMAC power rails inside the Ethernet Crate Controller. The output of this circuit is connected to the processor’s non–maskable interrupt line, through a gate which may be controlled by the processor via one of the Control Register output lines.