急求解决，omapl138 upp问题

FPGA与omapl138  upp连接，只是用upp接收fpga采样数据，为什么每次只能接收到一包数据，求解惑，程序如下：

#include <stdio.h>
#include "types.h"
#include "evmomapl138lin.h"
#include "evmomapl138_uPP.h"
#include "evmomapl138_i2c.h"
#include "evmomapl138_timer.h"
#include "evmomapl138_i2c_gpio.h"
#include "evmomapl138_gpio.h"
#include "evmomapl138_emac.h"
#include "uartStdio.h"
#include "uart.h"
#include "psc.h"
#include "hw_psc_OMAPL138.h"
#include "soc_OMAPL138.h"
#include "interrupt.h"
/*
* hello.c
*/

//uint16_t recBuf[1539] = {0};
#pragma DATA_SECTION(FPGA_ADC_DATA,".FPGA_ADC_upp");
#pragma DATA_ALIGN(FPGA_ADC_DATA, 8);

volatile uint16_t FPGA_ADC_DATA[5][1539] = {0};

//配置uPP
void uPP_config(void);

void send_GDB_HEX ();

void main(void)
{
#if NO_GEL
EVMOMAPL138_init();
EVMOMAPL138_initRAM();
#endif
uint16_t count = 0;

UPXS2_t * UPIS2r = (UPXS2_t *)&(UPP->UPIS2);//DMA I通道状态
   //UPXS2_t * UPQS2r = (UPXS2_t *)&(UPP->UPQS2);//DMA Q通道状态
   //UPISR_t * UPISR = (UPISR_t *)&(UPP->UPISR);//Up中断原始状态寄存器 1 EOLI线条结束标志、 EOWI窗口结束标志

USTIMER_init();
//USTIMER_delay(1000000);
//USTIMER_set(1000000);

uPP_config();

//我将upp的dma描述寄存器每次重写，为什么fpga连续发数据DSP只得到一包数据FPGA_ADC_DATA[0]，

//此时暂停运行发现程序停止在while(UPIS2r->bits.PEND == 1){};貌似下一包数据的存储地址没有被写入一直在等待，还有UPIS2r->bits.PEND位何时便为零？是否是在第一包数据到来时，dma开始传输，UPIS2r->bits.PEND == 0；同时第二包数据的dma地址被写入寄存器，然后.pend=1，等待第二包数据传输，然后依次类推呢？
while(1)
{

UPP->UPID0 = (uint32_t)&FPGA_ADC_DATA[count]; //add next DMA transfer//数据存储在FPGA_ADC_DATA中
UPP->UPID1 = 0x00010C06; //1 lines 3078 bytes per line 
UPP->UPID2 = 0x00000C06; //no offset between lines ；
while(UPIS2r->bits.PEND == 1){};
printf("\t\n count=%d\t\n",count);
count++;
if(count==5)
 {
   count=0;
  }

    printf("\t\n Reach the end of window \t\n");
}
}

void uPP_config()
{
upp_config_t config;

//UPCTL
config.UPCTL.value=0;
//config.UPCTL.bits.IWB = 1; //16 bit interface
//config.UPCTL.bits.DPWB = 2; //10 bit data
//config.UPCTL.bits.DPFA = 0; //对齐方式
config.UPCTL.bits.DPWA = 0; //位宽
config.UPCTL.bits.IWA = 1; //0 8bit 1 16bit
config.UPCTL.bits.DRA = 0; //通道A数据率 0 单 1双

config.UPCTL.bits.SDRTXIL = 0; //单数据率下的DMA乒乓模式 1 只有A通道乒乓
config.UPCTL.bits.DDRDEMUX = 0;

config.UPCTL.bits.CHN = 0; //1 dual channel mode 0 signal channel mode
config.UPCTL.bits.MODE = 0; //0 all recv, 1 all xmit, 2 a recv b xmit, 3 a xmit b recv
//Channel A ADC, Channel B DAC
//UPICR
config.UPICR.value=0;
config.UPICR.bits.CLKDIVA = 0;//15; //Set DAC sampling freqency at 75/16 Mhz (4.6875MHz)
config.UPICR.bits.STARTA =1;
config.UPICR.bits.ENAA =1;
//config.UPICR.bits.WAITA =1;
//UPIVR
config.UPIVR.value=0;
//config.UPIVR.bits.VALA = 0x1000;
//config.UPIVR.bits.VALB = 0x0000;

//UPTCR
config.UPTCR.value=0; //发送模式数据量门限、DMA触发门限设置all values 0 for 64byte DMA bursts read / write
//UPDLB
config.UPDLB.value=0; //no loopback
//UPIES
config.UPIES.value=0; //dont enable any interrupts
//UPPCR
config.UPPCR.value = 0;
config.UPPCR.bits.EN = 1; //enable uPP
config.UPPCR.bits.RTEMU = 1; //allow emulator use
config.UPPCR.bits.SOFT = 1; //allow emulation
UPP_init(&config);
}

//发串口数据，以16进制发送
void send_GDB_HEX ()
{
}