Campbell Hausfeld SM4M - Manual (Page 11)

Section 1. SM4M/SM16M Storage Module Overview
1-5
1.4.4 Memory Configuration
The Storage Module’s memory can be configured as either Fill and Stop or Ring
memory. In the Fill and Stop configuration, the Storage Module stops accepting
data when its memory is full. No data write-over occurs with this configuration. In
the Ring Memory configuration (the default setting), new data continues to be
stored even after the memory is full. Once full, new data is written over the oldest
data. The Storage Module’s memory configuration can be changed using SMS or
with command 4 of the CR500/510, CR10/10X and CR23X *9 Mode.
1.4.5 Baud Rates
The Storage Module automatically detects the baud rate of data sent to it.
When using the telecommunications commands, sending several carriage returns
will cause the Storage Module to match the computer’s baud rate (see
specifications above).
1.4.6 File Marks
File Marks are used to separate data in the Storage Module. A File Mark is
automatically placed in the SM’s memory when the SM is connected to a power
source (datalogger or retrieval interface) or when the datalogger compiles a
program containing Instruction 96. For example, if the user has retrieved data
from one datalogger, disconnects the SM and then connects it to a second
datalogger, a File Mark is placed in the data when the second datalogger is
connected. This mark follows the data from the first datalogger and precedes the
data from the second. A File Mark can also be inserted under program control.
The SM must be disconnected from power for a minimum of
10 seconds to be certain it places a File Mark in the SM when
reconnected.
A File Mark can be placed in the data by using SMS or the CR500/510,
CR10/10X or CR23X *9 Mode command 3. The Storage Module will not store
back-to-back file marks; if a File Mark is the last thing stored in memory, a
second file mark will not be stored.
1.4.7 Power-up Status Indication
When power is applied to the Storage Module by plugging it into a datalogger or
SC532, the red “Status” LED will flash to indicate the status of the module.
The SM must be disconnected from power for a minimum of
10 seconds to ensure it powers down and performs the status
check when reconnected.
After connection there will be a short delay when neither LED is illuminated. The
length of the delay is variable and is partly determined by the address of the
module. This delay avoids excessive power consumption during power-up, when
several modules are connected to the datalogger. For a module at address 1 the
initial delay will be up to 2 seconds. The delay increases by approximately one
second for each increase in the address number.
CAUTION
CAUTION