编码器技术方向调整，不需要交换AB信号

Signed-off-by: huhui <huhui@sharkgulf.com>

Applications/bsp/enc_intf.c

@@ -66,7 +66,7 @@ void enc_intf_quadrature_init(u32 rate) {
 	timer_icinitpara.icpolarity  = TIMER_IC_POLARITY_RISING;
 	timer_input_capture_config(timer,TIMER_CH_1,&timer_icinitpara);
 
-	timer_quadrature_decoder_mode_config(timer ,TIMER_ENCODER_MODE2,TIMER_IC_POLARITY_RISING, TIMER_IC_POLARITY_RISING);
+	timer_quadrature_decoder_mode_config(timer ,TIMER_ENCODER_MODE2,TIMER_IC_POLARITY_FALLING, TIMER_IC_POLARITY_RISING);
 	
 	/* auto-reload preload enable */
 	timer_auto_reload_shadow_enable(timer);