main.cpp

00001 #include <string>
00002 #include <iostream>
00003 #include <iomanip>
00004 
00005 /**
00006  * Tests were done with schema proposed here: DS11195C-page 11 FIGURE 2-25: Potentiometer Divider Non-Linearity Error Test Circuit (DNL, INL)
00007  */
00008 #include "MCP4xxxx_SPI.h"
00009 
00010 struct UserChoice {
00011     char choice;
00012     unsigned char moduleId;
00013 };
00014 
00015 /*
00016  * Declare functions
00017  */
00018 void AvailableIndicator(); // LED1 flashing for program while program is alive
00019 UserChoice DisplayMenuAndGetChoice(); // Display and get the user choice
00020 
00021 /*
00022  * Declare statics
00023  */
00024 DigitalOut g_availableLed(LED1); // To verify if program in running
00025 Ticker g_available; // LED1 will flash with a period of 2s
00026 #define __MANAGE_CS__ // /CS managed by application
00027 #undef  __MANAGE_CS__ // /CS managed by library
00028 #if defined(__MANAGE_CS__)
00029 DigitalOut g_chipSelect(p8); // /CS to select MCP4xxxx device
00030 CMCP4xxxx_SPI g_digitalPot(p5, p6, p7, NC, NC, NC); // Create an instance of the class CMCP4xxxx_SPI, p5/p6/p7: SPI#1, /CS managed by application, /RESET input not connected, , /SHDN input not connected
00031 #else // __MANAGE_CS__
00032 CMCP4xxxx_SPI g_digitalPot(p5, p6, p7, p8, NC, NC); // Create an instance of the class CMCP4xxxx_SPI, p5/p6/p7: SPI#1, /CS managed by library, /RESET input not connected, , /SHDN input not connected
00033 #endif // __MANAGE_CS__
00034 UserChoice g_userChoice; // Used to store user choice from displayed menu
00035 
00036 int main() {
00037 
00038     unsigned char potLevel = 0x80; // Initial digital potentiometer value
00039     
00040 #if defined(__MANAGE_CS__)
00041     g_chipSelect.write(1); // Disable chip
00042 #endif // __MANAGE_CS__
00043 
00044     // Launch available indicator
00045     g_available.attach(&AvailableIndicator, 2.0);
00046     
00047     while (true) {
00048     
00049         g_userChoice = DisplayMenuAndGetChoice(); // Retrieve the user selection
00050          switch (g_userChoice.choice) {
00051             case 'a':
00052                 potLevel += 1;
00053 #if defined(__MANAGE_CS__)
00054                 g_chipSelect.write(0);
00055 #endif // __MANAGE_CS__
00056                 g_digitalPot.Write(CMCP4xxxx_SPI::WriteToPot1, potLevel);
00057 #if defined(__MANAGE_CS__)
00058                 g_chipSelect.write(1);
00059 #endif // __MANAGE_CS__
00060                 break;
00061             case 'b':
00062                 potLevel += 1;
00063 #if defined(__MANAGE_CS__)
00064                 g_chipSelect.write(0);
00065 #endif // __MANAGE_CS__
00066                 g_digitalPot.Write(CMCP4xxxx_SPI::WriteToPot2, potLevel);
00067 #if defined(__MANAGE_CS__)
00068                 g_chipSelect.write(1);
00069 #endif // __MANAGE_CS__
00070                break;
00071             case 'c':
00072                 potLevel -= 1;
00073 #if defined(__MANAGE_CS__)
00074                 g_chipSelect.write(0);
00075 #endif // __MANAGE_CS__
00076                 g_digitalPot.Write(CMCP4xxxx_SPI::WriteToPot1, potLevel);
00077 #if defined(__MANAGE_CS__)
00078                 g_chipSelect.write(1);
00079 #endif // __MANAGE_CS__
00080                 break;
00081             case 'd':
00082                 potLevel -= 1;
00083 #if defined(__MANAGE_CS__)
00084                 g_chipSelect.write(0);
00085 #endif // __MANAGE_CS__
00086                 g_digitalPot.Write(CMCP4xxxx_SPI::WriteToPot2, potLevel);
00087 #if defined(__MANAGE_CS__)
00088                 g_chipSelect.write(1);
00089 #endif // __MANAGE_CS__
00090                 break;
00091             case 'e':
00092                 potLevel -= 1;
00093 #if defined(__MANAGE_CS__)
00094                 g_chipSelect.write(0);
00095 #endif // __MANAGE_CS__
00096                 g_digitalPot.Write(CMCP4xxxx_SPI::ShutdownPot1);
00097 #if defined(__MANAGE_CS__)
00098                 g_chipSelect.write(1);
00099 #endif // __MANAGE_CS__
00100                 break;
00101             case 'f':
00102                 potLevel -= 1;
00103 #if defined(__MANAGE_CS__)
00104                 g_chipSelect.write(0);
00105 #endif // __MANAGE_CS__
00106                 g_digitalPot.Write(CMCP4xxxx_SPI::ShutdownPot2);
00107  #if defined(__MANAGE_CS__)
00108                 g_chipSelect.write(1);
00109 #endif // __MANAGE_CS__
00110                 break;
00111             case 'r':
00112                 g_digitalPot.Reset();
00113                 break;
00114             default:
00115                 std::cout << "Invalid user choice\r" << std::endl;
00116                 break;
00117          } // End of 'switch' statement
00118        
00119     } // End of 'while' statement
00120 } // End of program - nerver reached
00121 
00122 void AvailableIndicator() {
00123     g_availableLed = !g_availableLed;
00124 } // End of AvailableIndicator
00125 
00126 UserChoice DisplayMenuAndGetChoice() {
00127     static UserChoice userChoice;
00128 
00129     // Display the title
00130     std::cout << "\r" << std::endl << "MCP4xxxx_SPI v0.1\r" << std::endl;
00131 
00132     // Display the menu
00133     std::cout << "\tIncrease level on pot #1:\t\t\ta\r" << std::endl;
00134     std::cout << "\tIncrease level on pot #2:\t\t\tb\r" << std::endl;
00135     std::cout << "\tDecrease level on pot #1:\t\t\tc\r" << std::endl;
00136     std::cout << "\tDecrease level on pot #2:\t\t\td\r" << std::endl;
00137     std::cout << "\tShutdown pot #1         :\t\t\te\r" << std::endl;
00138     std::cout << "\tShutdown pot #2         :\t\t\tf\r" << std::endl;
00139     std::cout << "\tReset MCP4xxxx          :\t\t\tr\r" << std::endl;
00140     std::cout << "Enter your choice: " << std::flush;
00141     userChoice.choice = getchar();
00142     // Display the menu
00143     std::cout << "\r" << std::endl << std::flush;
00144     return userChoice;
00145 }