I’m trying to use the writetopipein() function to send data through a pipein to the fifo in my FPGA design but I don’t quiet understand this function:
function success = writetopipein(obj, epaddr, epvalue, psize)
%WRITETOPIPEIN Write data into a PipeIn.
% SUCCESS=WRITETOPIPEIN(OBJ,epADDR,epVALUE) writes
% the elements of the vector epVALUE into a PipeIn endpoint.
% The elements of epVALUE need to be unsigned bytes (8 bits : 0…255)
% stored as fints (floating point integers).
% epADDR the endpoint address of the PipeIn endpoint.
%
% SUCCESS=WRITETOPIPEIN(OBJ,epADDR,epVALUE,PSIZE) subdivides
% transfer into multiple packets. The PSIZE contains the
% packet size of each packet, except for the last one.
%
% The valid endpoint address ranges are:
%
% 0x00-0x1F : WireIn
% 0x20-0x3F : WireOut
% 0x40-0x5F : TriggerIn
% 0x60-0x7F : TriggerOut
% * 0x80-0x9F : PipeIn
% 0xA0-0xBF : PipeOut
%
% Copyright © 2005 Opal Kelly Incorporated
% Rev Date
bsize = prod(size(epvalue));
if ~exist(‘psize’ ,‘var’) | isempty(psize); psize = bsize; end;
psize = min(psize,bsize);
if (bsize == psize),
success = calllib(‘okFrontPanel’, ‘okFrontPanel_WriteToPipeIn’, obj.ptr, epaddr, psize, epvalue);
else
kk = (1:psize)’;
for k = 1:fix(bsize/psize),
success = calllib(‘okFrontPanel’, ‘okFrontPanel_WriteToPipeIn’, obj.ptr, epaddr, psize, epvalue(kk));
kk = kk+psize;
end
psize_last = mod(bsize,psize);
kk = kk(1:psize_last);
success = calllib(‘okFrontPanel’, ‘okFrontPanel_WriteToPipeIn’, obj.ptr, epaddr, psize_last, epvalue(kk));
end
I don’t understand what does it mean “subdivides transfer into multiple packets.” and how should I set the psize? For example now I have an input data array which has 16 items and each item is 32 bits wide.