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PLUG-IN CARDS

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GENERAL PAGE

Model 10BACIA
Auxiliary Computer Interface Card

Model 10BACI-422 RS422
Auxiliary Computer Interface Card

Model 10BACI-488 IEEE-488
Auxiliary Computer Interface Card

	Model 10BACIA Auxiliary Computer Interface Card
	Model 10BACI-422 RS422 Auxiliary Computer Interface Card
	Model 10BACI-488 IEEE-488 Auxiliary Computer Interface Card

Model 10BACIA Auxiliary Computer Interface Card [Back ]

This card permits any System 10 "B-sized" mainframe to establish simultaneous high-speed communications with more than one external RS232 device (computer, terminal, buffered printer, recorder, etc.).

Each 10BACIA supplies an independent "auxiliary" full-duplex RS232 interface, operating with its own user-specified "protocol" characteristics.  The number of 10BACIA cards a mainframe may contain is limited only by the number of available "B Slots" (see Mainframe Table).

As seen by a connected external RS232 device, an "auxiliary" interface port behaves identically to the mainframe's standard Computer Interface Port.  That is, a standard mnemonic command issued to a 10BACIA by the connected device will invoke a response identical in form to that produced by the Computer Interface Port to the same command.

For example, a DUMP (DMP) command issued to a 10BACIA will cause it to "dump" data; a SEND (SND) command will cause it to "send" the specified message; a COLUMNS (CLM) command will establish columnar format for subsequent "stream" and "hardcopy" outputs from that 10BACIA; and so on.

While the activity of a given "auxiliary" interface port can be directly controlled by the external RS232 device to which it is connected, it can also be controlled by commands entered through the mainframe's plug-in keyboard or Computer Interface Port.  Such control can be effected by one of three "run-time" commands: ATTACH (ATT), VIA (VIA), or COMMUNICATIONS (COM).  The ATT and VIA commands serve to route operator- or computer-entered commands directly to a given 10BACIA.  The COM command designates a "Default Communications Port" for the mainframe.  This is a single system RS232 interface port which will respond to all subsequent port-related commands received by the mainframe.

The Model 10BACIA responds to the System 10 FRAME CHANNELS (FCH) command.  This command allows a time-coherent "frame" of data for a specified range of channels to be transferred to the 10BACIA's output buffer as soon as this data set has been fully scanned and posted.  During loading of the buffer, the 10BACIA will delay responding to a request for output until the loading has been completed (about 5 milliseconds).  If the 10BACIA is in the process of transmitting data at the end of the scan cycle, loading is suspended.  The currently loaded "buffer frame" of data can be subsequently transmitted from the 10BACIA via any of the standard channel-outputting commands.

The Model 10BACIA is a system COPROCESSOR.  In addition to an auxiliary RS232 interface, it also provides an on-board DATA RAM.  Externally acquired numeric and logic data can thus be downloaded from the connected RS232 device to the 10BACIA itself.  With each internal scan cycle, this data will be locally updated (at the 10BACIA) and will be read from there by the system Central Processor.  Such local handling of downloaded data by the 10BACIA helps preserve the mainframe's high scan speed when a large number of inputs is involved.

Front-edge LED status indicators similar to those on the mainframe's Model 10BIP232 Interface Card let you monitor line and command activity at each auxiliary interface port.  In addition, a 10BACIA's COM indicator will light when that card has been designated to be the mainframe's "Default Communications Port."

Model 10BACI-422 RS422 Auxiliary Computer Interface Card [Back ]

The Model 10BACI-422 is equivalent to a Model 10BACIA with an integral RS422 hardware interface on a 9-pin subminiature female socket (in place of the 10BACIA's standard RS232 interface).

The RS422 interface includes an extra pair of wires for communication of an external synchronizing pulse.  This allows timed synchronous data collection, controlled by a master timing pulse.  The 10BACI-422 is particularly useful in conjunction with the Model 10K488 Data Concentrator, since it allows the timing pulse generated by the 10K488 to synchronize the collection of data for all connected System 10 mainframes.

Like the 10BACIA, the 10BACI-422 will respond to the FRAME CHANNELS (FCH) command, to allow transmission of a time-coherent "frame" of data for a specified range of channels.

When an external synchronizing pulse signal is available through the RS422 interface—as it is when the 10BACI-422 is communicating with a Model 10K488 Data Concentrator—then you will need to enter a CLOCK (CLK) command and a MASTER TIMING CLOCK (MTC) command in order to "slave" the mainframe's scan cycle to this "master" pulse signal.*  The external sync pulses must be at a rate of 1 second ± 0.05%.

* The purpose of the CLOCK (CLK) command is to synchronize the scanning of data channels to the mainframe's time-of-day clock.  The purpose of the MASTER TIMING CLOCK (MTC) command is to synchronize the mainframe's time-of-day clock to the externally sourced timing pulse, to within ±2 milliseconds.  The synchronized millisecond clock is then used to trigger successive scans at 0.1-second intervals, as directed by the CLK command.  MTC should be applied to one and only one Model 10BACI-422 in the system, since it in effect tells the Central Processor which 10BACI-422 to "listen to" for each successive sync pulse.

Model 10BACI-488 IEEE-488 Auxiliary Computer Interface Card [Back ]

The Model 10BACI-488 is equivalent to a Model 10BACIA with a 24-pin parallel port for standard TALKER/LISTENER communications with an IEEE-488 bus (in place of the 10BACIA's standard RS232 interface).

Special front-panel LAD ("Listener Active Device") and TAD ("Talker Active Device") lights continuously indicate the System 10's current bus role.  There are on-board DIP switches for assigning a specific bus address to the System 10.  Note also that the rear connector supplied with the 10BACI-488 covers two mainframe "B slots."

While the 10BACI-488 conforms to the hardware protocol of IEEE-488, it employs a proprietary software protocol.  Also, the data transfer rate is limited by the rate at which data can be received from the System 10 database (typically 2500 to 3000 channels per second).  As a result, the 10BACI-488 transfer rate will normally be about 15,000 to 17,000 bytes per second.

Two additional commands have been developed for use with the 10BACI-488: ADDRESS (ADD), which lets you read the current bus address setting, and END OR IDENTITY (EOI), which lets you invoke the "END OR IDENTIFY" function at the end of each output line and/or at the end of each complete output transmission.*

Like the 10BACIA, the 10BACI-488 will respond to the FRAME CHANNELS (FCH) command, to allow transmission of a time-coherent "frame" of data for a specified range of channels.

Optional floating-point data conversion is available for the 10BACI-488 (only).  This allows the card to issue data for all scanned channels or for a specified range of channels in either IEEE or DEC floating-point format.  Contact the factory for details on this option.

* When large blocks of data are being routinely placed on the bus—as would happen, for instance, in response to a DUMP (DMP) command—it would optimize speed to have EOI occur only at the end of every complete transmission, and not at the end of every output line.