How to set load capacity for L6470?

[PDhak]

I m using L6470 which is working fine without load, but when load is applied the motor stuck. Which parameter i should consider for it?

also how to reduce stepper motor noise?

My current configuration are like this

write_buffer[0]=CMD_SETPARAM |REG_MAX_SPD;
 write_buffer[1]=0x00;
 write_buffer[2]=0x30;
 write_buffer[3]=0;
 write_cmd(&write_buffer[0],4);
 
 read_cmd(CMD_GETPARAM | REG_MAX_SPD,&read_buffer[0]);
 
 delay(10);
 
 write_buffer[0]=CMD_SETPARAM |REG_FS_SPD;
 write_buffer[1]=0x0;
 write_buffer[2]=0x40;
 write_buffer[3]=0;
 write_cmd(&write_buffer[0],4);
 
 write_buffer[0]=CMD_SETPARAM |REG_ACC;
 write_buffer[1]=0x01;
 write_buffer[2]=0xAA;
 write_buffer[3]=0;
 write_cmd(&write_buffer[0],4);
 
 read_cmd(CMD_GETPARAM | REG_ACC,&read_buffer[0]);
 
 delay(10);
 
 write_buffer[0]=CMD_SETPARAM |REG_DEC;
 write_buffer[1]=0x0F;
 write_buffer[2]=0xAA;
 write_buffer[3]=0;
 write_cmd(&write_buffer[0],4);
 
 read_cmd(CMD_GETPARAM | REG_DEC,&read_buffer[0]);
 
 delay(10);
 
 
 write_buffer[0]=CMD_SOFT_HIZ;
 write_buffer[1]=0;
 write_buffer[2]=0;
 write_buffer[3]=0;
 write_cmd(&write_buffer[0],4);
 delay(10);
 
 write_buffer[0]=CMD_SETPARAM|REG_STEP_MODE;
 write_buffer[1]=1;
 write_buffer[2]=0;
 write_buffer[3]=0;
 write_cmd(&write_buffer[0],4);
 
 delay(10);
 
 read_cmd(CMD_GETPARAM | REG_STEP_MODE,&read_buffer[0]);
 
 write_buffer[0]=CMD_RESET_POS;
 write_buffer[1]=0;
 write_buffer[2]=0;
 write_buffer[3]=0;
 write_cmd(&write_buffer[0],4);
 
 delay(10);
 
 read_cmd(CMD_GETPARAM | REG_ABS_POS,&read_buffer[0]);