What kind of disk drives can I use with the CL160?
The CL160 works best with Seagate Cheetah or Hitachi Ultrastar SCSI drives. Both 68pin and 80pin drives are supported, the latter requires a SCSI backplane. You can expect a throughput of 35MB/s per drive with 10,000RPM, and 45MB/s per drive with 15,000RPM
What is the relationship between frame size, sequence size and the number of frames recorded?
Frame size refers to the size of a raw camera frame. Keep in mind that the CLFC uses "perfect" bit-packing, so a 10-bit 1024x1024 image is only 1,310,720 bytes. The frame size may range from a few kilobytes to tens of megabytes, however disk-write operations are optimized for roughly 3.5 MB. To ensure maximum record bandwidth, camera frames are either merged or split so that the optimal size write can be performed. A single disk write operation is called a "sequence". Consider two cases. Case 1: A camera has a 1.25 MB frame, split across 4 channels. The size per channel is 327680 bytes. Therefore, 11 frames will be combined into each sequence. Case 2: A camera has a 16 MB frame, recording to 1 channel. The frame will be split into 5 3.5 MB frames (the last being only partially used). When a frame is split into multiple sequences, we call this "fragmented" or "multi" writes. Many DVR Express operations must be aligned to sequence boundaries. In the fragmented case, this does not restrict the user. In the traditional case however, this has several implications. The number of frames recorded must always be a multiple of the sequence size. Since a write does not occur until 11 frames have been acquired, no frames are reported as "recorded" until all 11 have been acquired. All pre-trigger boundaries must also be aligned to sequence boundaries. The CLFC administrator option "Max Disk Write Size" sets the ideal size of a disk-write. Users may change this option to tweak the sequence size used but keep in mind that the disk bandwidth may be reduced also. Users may also force a sequence size by specifying "WRITESIZEBLOCKS" in their camera files.
I believe I require technical support, what information should I be ready to provide?
The DVR Express maintains a log of system activity. It is almost always the first piece of information that technical support will require. You may locate the CLFC log in [DVR Express Install Path]\ClfcLog.txt. If the default install path was used, the file will be in c:\Program Files\IO Industries\DVR Express\CLFC\ClfcLog.txt. Also found in the same directories, it may be useful to send the files "FileTable_Verification_Results.txt" and "ClfcInfo.txt". Always be ready to provide a history describing all significant steps up to and including the suspected issue. Provide all of the above in an email to your support contact ([email protected] by default). Following these steps will help ensure a prompt and efficient solution to most problems.
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