VCP2 for frame length larger than 256 and soft decision

Hello everybody,

My goal is to process convolutional coded data using VCP2 coprocessor in DSP C6474 (which should be identical to 6488).  Here is my VCP2 basic parameter setting:

 VCP2BASEPar.frameLen                    = FL;  

VCP2BASEPar.rate                             = 2;     

VCP2BASEPar.constLen                     = 9;                 

VCP2BASEPar.yamTh                        = 0;

VCP2BASEPar.stateNum                    = 0;

VCP2BASEPar.decision                      = VCP2_DECISION_SOFT;

VCP2BASEPar.readFlag                     = 0;

VCP2BASEPar.tbConvrgMode           = 0;

VCP2BASEPar.tailBitEnable                = 0;

VCP2BASEPar.traceBackIndex          = 0;

VCP2BASEPar.outOrder                    = 0;

VCP2BASEPar.perf                            = VCP2_PERF_MOST_CRITICAL;

When I select the FL less than 256, my code works and I get the expected results. However for the same code but FL > 256, VCP2’s behavior is not the same. It seems it never finishes the processing of the data, i.e,  VCP2_statRun() always returns 1.

 I am wondering if somebody has some insight into this problem.

 Thank you,