修改了后退的逻辑

system/gpio/gpio_pwm_tank0202.c

@@ -171,18 +171,20 @@ void mode_right_back(unsigned char gval) {
 int  tank0202_change(unsigned char *buf) {
     unsigned char mode = buf[1];
     unsigned char val = buf[2];
-    if(mode == 1 && modecount==0) {
+    if(mode == 1 ) {
         //mode_lift_flont(val);
         mode_right_flont(val);
+		modecount=0;
     }else if(mode == 2) {
         //mode_lift_back(val);
         mode_right_back(val);
+		modecount=1;
     }else if(mode == 3) {
-         mode_lift_back(val+25);
-        //mode_right_flont(80);
+        if(modecount == 0) mode_lift_back(val+25);
+        if(modecount == 1) mode_lift_flont(val+25);
     }else if(mode == 4) {
-        mode_lift_flont(val+25);
-        //mode_right_back(80);
+        if(modecount == 0) mode_lift_flont(val+25);
+        if(modecount == 1) mode_lift_back(val+25);
     }
     
 }
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