Campbell CSM1, Instruction Manual

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A-1
Appendix A. 9-Pin Storage Module
Interface
Pin 1 (input) 5V supply to CSM1. The minimum voltage for
operation is 4.85V. Below approximately 4.85V the
CSM1 will neither accept data nor communicate; it is
disabled. The only time that this may cause a problem is
when using Campbell Scientific equipment with the
PC201 card. This uses the PC 5V supply to power the
module. The 5V supply of some PCs may not be set up
accurately and be below the minimum voltage for
operation of the CSM1. If this is the case you should
use another PC or have the PC power supply adjusted.
For powering the CSM1 this power supply must be
capable of supplying up to 18mA continuously, with
peaks of up to 100mA.
Pin 2 Power and signal ground
Pin 3 (input) Ring indicate (not used by module)
Pin 4 (output) CSM1 Transmit Data line (TxD). In
telecommunications mode data is transmitted to the
computer on this line. Data is transmitted
asynchronously at levels of 0-5V DC. The idle state is
0V. This line is held high to indicate that the CSM1 can
accept data, when receiving data from 21X and CR7
dataloggers.
Pin 5 (input) Modem Enable line. The module uses this line to detect
other communications activity on the datalogger serial
port. When this line is high, the CSM1 does not attempt
to communicate.
Pin 6 (input) Printer Enable/Serial Device Enable line. In
combination with line 7 this is used by the datalogger to
wake up the CSM1 to receive data. The mode of
operation depends on the datalogger type (see
datalogger manual for further details). To force the
CSM1 into telecommunications mode this line must be
taken high with line 7.
Pin 7 (input/output) Clock/Handshake line. For the CR10, this line is used in
conjunction with line 6 to control transfer of data to the
CSM1. For telecommunications mode this must be
taken high before, or at exactly the same time as pin 6.
Pin 8 (input) Not used
Pin 9 (input) CSM1 Receive Data line (RxD). Data transmitted from
a datalogger or computer is received on this line.