MULTITASKER
7.3 RS-232 CONNECTION
7.3.1 RS-232 COMMUNICATION
If a control system is used to control the cards in the MultiTasker, connect the
The cable must have the appropriate connector on each end and the internal wiring must be correct. Connectors typically have 9 pins
Figure 1 shows the typical pinout and connections for a DB-9 computer serial port and Figure 2 shows the typical pinout and connections required for a DB-25 computer serial port.
MultiTasker |
| Computer | ||
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| 5 |
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GND | 5 | GND |
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2 | 2 |
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TXD | RXD |
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3 | 3 |
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RXD | TXD |
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Figure 1: DB-9 Serial Connection
7.4 RS-232 PROTOCOL
The
1.Brackets “[ ]” are part of the command for the controller or
2.Brackets "{ }" are part of the command for the panel display commands.
3.Use uppercase letters for all commands.
The
Baud Rate | = | 9600 |
Data Bits | = | 8 |
Stop Bits | = | 1 |
Parity | = | None |
The enclosure and cards in a MultiTasker are capable of performing various functions, as well as providing feedback to the user or control system. Commands instruct a card to perform specific actions, request status information, and some do both simultaneously.
MultiTasker
GND | 5 | 7 |
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TXD | 2 | 3 |
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RXD | 3 | 2 |
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Computer
GND
RXD
TXD
A command that does not request specific information will generate feedback of “[ ]”. The open bracket immediately followed by a closed bracket indicates the card or unit received a valid command. If the command requested information from the card or enclosure, the feedback generated is the acknowledgement of having received a valid command. Invalid commands generate feedback that includes “ERR” plus an error code.
Figure 2: DB-25 Serial Connection
Example: [ERR001]
Commands ending in “S” will be saved into memory. Commands not ending in “S” will still be executed, but will not be restored when the system is reset or powered-off, then on.
9 |