Diff: main.cpp

Revision:

1:862d95c7ca2c

Parent:

0:1ec32b38f724

--- a/main.cpp	Wed Jun 25 02:25:16 2014 +0000
+++ b/main.cpp	Wed Jul 24 12:12:14 2019 +0000
@@ -1,38 +1,71 @@
+/* Quick and dirty program to receive keystrokes and send text via virtual
+ * serial port, it also flashes the green led with 1 millisecond pulses as
+ * life indicator
+ *
+ * Unfortunally the mbed lib sends an error via serial when PwmOut is used
+ *
+ * This program has been derived from
+ * https://os.mbed.com/users/Bongjun/code/LPC11U68_USBSerial/
+ *
+ */
+
 #include "mbed.h"
-#include "USBSerial.h"
 
-DigitalOut myled1(LED1);
-DigitalOut myled2(LED2);
-DigitalOut myled3(LED3);
+DigitalOut LED_rd(LED1);
+DigitalOut LED_gn(LED2);
+DigitalOut LED_bl(LED3);
+/*
+// PwmOut: mbed lib raises an error: no available SCT, even LED pins provide PWM
+    PwmOut LED_rd(LED1);
+    PwmOut LED_gn(LED2);
+    PwmOut LED_bl(LED3);
+    float brightness_LED_rd = 0.8;
+    float brightness_LED_gn = 0.4;
+    float brightness_LED_bl = 0.2;
+*/
 
 //Virtual serial port over USB
-USBSerial serial;
 Serial pc(USBTX, USBRX);
 
+volatile uint8_t    buf[] = {'\0', '\0'};   // buf[1]: string null terminator
+
+void onCharReceived()   // fills character buffer using rx interrupt
+{
+    buf[0] = pc.getc();
+}
+
 int main()
 {
-    uint8_t buf[1];
-    while(1) {
-//        pc.printf("I am a PC serial port\r\n");
-        serial.printf("I am a virtual serial port\r\n");
+    LED_rd = LED_gn = LED_bl = 1;           // LEDs off
+    pc.baud(115200);                        // from default = 9600
+    pc.attach(&onCharReceived);
+    pc.printf("\r\n\n\n#####  LPCXpresso11U68_USBSerial  #####\r\n\r\nPress any key at the PC keyboard!\r\n\r\n");
 
-        //if data is exist
-        if (serial.available()) {
-            buf[0] = serial._getc();
-            serial.printf("recv char is 0x%.2x\r\n", buf[0]);
-        }
+    while(1) {
+//uint32_t            counter = 0;            // Debug only
+//        pc.printf("%8d\r\n", counter++);    // Debug only
 
-        myled1 = 1;
-        wait(0.2);
-        myled1 = 0;
-        wait(0.2);
-        myled2 = 1;
-        wait(0.2);
-        myled2 = 0;
-        wait(0.2);
-        myled3 = 1;
-        wait(0.2);
-        myled3 = 0;
-        wait(0.2);
+        switch(buf[0])
+        {
+            case '\0':
+                break;
+            case 'a':
+                pc.printf("recv char IS THE EXPECTED 'a' = 0x%.2x\r\n", buf[0]);
+                break;
+            case 'b':
+                pc.printf("recv char IS THE EXPECTED 'b' = 0x%.2x\r\n", buf[0]);
+                break;
+            default:
+                pc.printf("recv char is not expected: ");
+                if (buf[0]<33)
+                    pc.printf("0x%.2x\r\n", buf[0]); // hex code, when non-printable char
+                else
+                    pc.printf("%s\r\n", buf);
+                break;
+        }
+        buf[0] = '\0';      // reset character buffer
+
+        LED_gn = 0; wait_ms(1);     // just one millisecond due to high brightness of green
+        LED_gn = 1; wait_ms(299);
     }
 }