csmstr - Omega Engineering

CRIMSON BASICS
DOWNLOADING TO THE MASTER
Note that some caution is required when mounting the CompactFlash card...
• When the card is mounted, the Master will periodically inform the PC if data on
the card has been modified. This means that both the PC and the Master will
suffer performance hits if the card is mounted during data logging operations for
longer than necessary.
• If you write to the CompactFlash card from your PC, the Master will not be able
to access the card until Windows releases its “lock” on the card’s contents. This
may take up to a minute, and will restrict data logging operations during that
time, and prevent access to custom web pages. Crimson will use the Master’s
RAM to ensure that no data is lost, but if too many writes are performed such
that the card is kept locked for four minutes or more, data may discarded. Note
that Windows 98 is particularly bad at keeping the card locked when there is no
need for it. Windows 2000 or Windows XP is thus the operating system of
choice when using this feature.
• You should never attempt to use Windows to format a CompactFlash card that
you have mounted via the Master, whether it be via Explorer or from the
command prompt. Windows does not correctly lock the card during format
operations, and the format may thus be unreliable and lead to subsequent data
loss. See below for details of how to format a card in a reliable manner.
FORMATTING THE COMPACTFLASH
The preferred method of formatting a card is via the Format Flash command on the Link
menu. Selecting this command will explain that the formatting process will destroy all the
data stored on the CompactFlash card and offer you a chance to cancel the operation. If you
elect to continue, the Master will be instructed to format the card. Note that this process may
take several minutes for a large card. Slow formats on Masters that are performing data
logging may therefore result in gaps in the recorded data.
A less attractive method of formatting a card is via a dedicated CompactFlash drive connected
to your PC. If you use this method, be sure to instruct Windows to format the card using
FAT16. For very small or very large cards, Windows will most likely choose the wrong
format by default. Worse still, some versions of Windows Explorer will not allow you to
override the default format, forcing you to use the command line version FORMAT instead.
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