/*
 Program for the Lecture 2.2.3
 This needs to be built with the board package of MBedOS 
 (Arduino MbedOS RP2040 boards --> Raspberry Pi Pico
 If you try to upload this program with other Pico board choices, 
 the board will become unresponsive.
 CAUTION1: I will explain the steps to recover reliably whenever 
 the program becomes unresponsive  because of wrong assembly programs 
 which may hang the board due to some errors in your program.
 CAUTION2: DO NOT UPLOAD this program with 
 Raspberry Pi RP2040 Boards (1.4.0) --> Raspberry Pi Pico
*/
#include<stdio.h>
#include<stdlib.h>

// Uncomment this if when you copy this code to run it on HW
//#define RUN_ON_HW

#ifdef RUN_ON_HW
#define Serial1 Serial
#endif

void myPrint(char* fnName, unsigned int result);

// Define external assembly function
extern "C" { 
  unsigned int add_asm_fn(void);
  unsigned int flags_add_asm_fn(void);
}

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  Serial1.begin(9600);
  pinMode(LED_BUILTIN, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {

  unsigned int add_ret_val;
  unsigned int flags_ret_val;

  add_ret_val = add_asm_fn();
  myPrint("add_asm_fn()", add_ret_val);

  flags_ret_val = flags_add_asm_fn();
  myPrint("flags_add_asm_fn()", flags_ret_val);


  digitalWrite(LED_BUILTIN, HIGH);
  delay(1000); 
  digitalWrite(LED_BUILTIN, LOW);    
  delay(1000); 

} // end of loop()

void myPrint(char* fnName, unsigned int printVal){
  Serial1.print("The value returned from the assembly fn ");
  Serial1.print(fnName);
  Serial1.print(" : "); Serial1.println(printVal);
  
  Serial1.print("The value returned from the assembly fn ");
  Serial1.print(fnName);
  Serial1.print(" in Hex: 0x"); Serial1.println(printVal, HEX);  
  Serial1.println(); // print an empty line
} // myPrint(char*, int)