Sigma LBA-500PC, LBA-710, LBA-714PC, LBA-300, LBA-712, LBA-708 manual 10.6.1.2 RDD? Read Frame Transfer

RCC FrameNumber=19; Row=11; #3512(DAW)…(DAW)(^END)

10.6.1.2 RDD? - Read Frame Transfer

To download a frame of data from the LBA-PC, you must send the RDD? command along with any optional parameter that identifies which frame you are requesting to transfer.

The frame parameter is optional and is numbered from -1 to n. ‘n’ is the number of frames in the frame buffer. Frame -1 is the Gain Frame, 0 is the Reference frame, and frames 1 to n are data captured in the frame buffer. If you do not send the frame number parameter then the current frame is used.

The frame data is sent as a modified IEEE 488.2 Definite Length Arbitrary Block Response Data. The number of bytes in a frame is two times the number of pixels. For example, a 128 X 120 frame consists of 30,720 bytes, a 256 X 240 frame consists of 122,880 bytes, etc. Each pixel is a sixteen-bit two’s complement fixed point value having the form:

siiiiiii ifffffff	LBA-300PC	-256 to 255.9921875
siiiiiii iiifffff	LBA-400PC	-1024 to 1023.96875
siiiiiii iiiiifff	LBA-500PC	-4096 to 4095.875
siiiiiii ifffffff	LBA-708PC	-256 to 255.9921875
siiiiiii iiifffff	LBA-710PC	-1024 to 1023.96875
siiiiiii iiiiifff	LBA-712PC	-4096 to 4095.875
siiiiiii iiiiiiif	LBA-714PC	-16384 to 16383.5

Where:

s	=	sign bit
i	=	integer
f	=	fraction

Use the :FST? command to determine the specific fixed point format of pixels in a frame. The PixelBits parameter specifies the number of integer bits. The PixelBitsFraction parameter specifies the number of fraction bits. To convert a sixteen bit fixed point data word to a floating point value, divide the data word by 2 raised to the power of PixelBitsFraction (128, 32, 8, or 2 for the LBA-300/708PC, LBA-400/710PC, or LBA-500/712PC, or LBA-714PC respectively).

The LBA-PC responds to the query by repeating RDD followed by three parameters specifying the frame number, number of data columns, and number of data rows. Next comes the definite length arbitrary block response data specification, which has the form:

#nd..d(DAW)…(DAW)

Where:
Operator’s Manual	189	LBA-PC
Doc. No. 10654-001, Rev 4.10