/*
 * Lab9_Params_Flags_asm_framework ... on 8 Oct 2021 (Fri, 9:30 am) - modified 
 * the function signature of the getMaxUnsigned()
 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 it while running on Wokwi Simulator
#define RUN_ON_WOKWI

#ifdef RUN_ON_WOKWI
#define Serial Serial1
#endif

void myPrint(char* fnName, int result);
bool resFlag = false;
int  resVal = 0;
unsigned uResVal = 0; // Newly added for receiving the value returned by getMaxUnsigned()

// Define external assembly function
extern "C" { // Implement the last three problems
  unsigned int get_cpsr0(void);
  unsigned int get_cpsr1(void);
  bool isEqual(int param1, int param2);  // It's implementation is given as a demo
  bool isNegative(int param1);
  int getMinSigned(int param1, int param2, int param3, int param4);  
  unsigned getMaxUnsigned(unsigned param1, unsigned param2, 
                          unsigned param3, unsigned param4);  
}


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

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

  unsigned int cpsr_val;

  digitalWrite(LED_BUILTIN, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(2000);     // Mouli                  // wait for a second
  digitalWrite(LED_BUILTIN, LOW);    // turn the LED off by making the voltage LOW
  delay(2000);     // Mouli                  // wait for a second


   cpsr_val = get_cpsr0();
   myPrint("get_cpsr0", cpsr_val);
/*  
  Serial.print("Calling the assembly program isEqual()\n");
  resFlag = isEqual(11, 11);
  myPrint("isEqual", (int)resFlag);

  Serial.print("Calling the assembly program isNegative()\n");
  resFlag = isNegative(+10);
  myPrint("isNegative", (int)resFlag);
  
  Serial.print("Calling the assembly program getMinSigned()\n");
  uResVal = getMinSigned(1, -2, -3, -4);  // With four parameters
  // Since uResVal size and int size are not different, no changes done to its contents
  // Before passing it to the myPrint function which prints the values
  myPrint("getMinSigned", (int)uResVal);  

  Serial.print("Calling the assembly program getMaxUnsigned()\n");
  // The below negative values are treated as higher positive values
  // 0xFFFF FFFF, 0xFFFF FFFE, 0xFFFF FFFD, 0xFFFF FFFE
  // With four parameters
  resVal = getMaxUnsigned((unsigned)1, (unsigned)2, (unsigned)3, (unsigned)-4);  
  myPrint("getMaxUnsigned", resVal); 
*/

} // end of loop()

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