6678 EDMA 的一点疑问

请问6678 EDMA的使用 只需要配置 channel 和 parasetup 就行了？？  这里的 instnum 指的是什么？？

static Int32 edma_ping_pong_xfer_gbl_region (Int32 instNum, Uint8 channelNum)
{    
    CSL_Edma3Handle                 hModule;
    CSL_Edma3Obj                    edmaObj;
    CSL_Edma3ParamHandle            hParamPing;
    CSL_Edma3ParamHandle            hParamPong;
    CSL_Edma3ChannelObj             chObj;
    CSL_Edma3CmdIntr                regionIntr;
    CSL_Edma3ChannelHandle          hChannel;
    CSL_Edma3ParamSetup             myParamSetup;
    CSL_Edma3Context                context;
    CSL_Edma3ChannelAttr            chAttr;
    CSL_Status                      status;
    Uint32                          loopIndex;

    /* Start the EDMA PING-PONG test over the Global Region. */
    printf ("Debug: Testing EDMA(%d) Ping-Pong Test (Global) Region for Channel %d...\n", instNum, channelNum);