Campbell SC32A, Справочное руководство

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SC32A Optically Isolated RS232 Interface
4
More information on addressing is given in the CR10 instruction
manual.
In most cases, if the SC32A is used between the CR10 and some peripheral (e.g. a
PC), and addressable peripherals are also present (e.g. a Storage Module), the
jumper should be in place. This will block addressing information from reaching
the SC32A interfaced peripheral. The only situation in which the jumper may
safely be removed is if the SC32A is interfacing the only peripheral attached to
the CR10 (with the exception of cassette tape).
1. Any printer-type peripheral interfaced to the CR10 through an
SC32A can be used as an addressable peripheral by using an
SDC99 Synchronous Device Interface. The SDC99 should be
connected between the SC32A and the datalogger. Data is
passed to the SC32A only if the SDC99 is addressed. After
being addressed, the SDC99 raises pin 6 of the SC32A; thus, the
jumper must be removed.
2. An SC32A may be used to interface a computer to a CR10
which also has an RF95 (in SDC state) attached. This is the
only situation in which two modems may be operating
simultaneously on one datalogger.
5.3 Special Cases
5.3.1 Null Modem
A null modem connection is required only if the RS232 device connected to the
SC32A is configured as Data Communications Equipment (DCE). Wiring
between two RS232 connectors for creating a null modem is shown in Table 2.
Table 2 Null Modem Configuration
SC32A Side RS232 Side
25-Pin Connector 25-Pin Connector
PIN # Connects To PIN #
1 1
7 7
2 3
3 2
6 20
4 and/or 20 To a line that
is logic high
The side of the null modem connected to the SC32A must be male.
The gender of the other side is dependent on the mating connector
going to the computer.
NOTE
NOTE
NOTE