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diff --git a/F2024/coe718/labs/lab1/report/report.md b/F2024/coe718/labs/lab1/report/report.md new file mode 100644 index 0000000..76c08fb --- /dev/null +++ b/F2024/coe718/labs/lab1/report/report.md @@ -0,0 +1,156 @@ +# Objective + +This lab project introduces Keil uVision IDE, and the development boards students will be using throughout the semester. +A general survey of features is accomplished by working with an input (joystick), +and several outputs (LEDs and LCD screen) of the development board. + +# Implementation + +This implementation elects to use the builtin joystick library +-- and GPIO libraries, as a dependency -- +provided by the Keil IDE rather than those provided in the lab manual, +in an effort to increase _integration_ with the IDE. + +<!--After following the lab manual instructions and copying over the files from the course directory,--> +<!--the project was analyzed for --> + +After inspecting the project following the lab manual instructions, +the joystick header was added to the `Blinky.c` file and initialized alongside the other peripherals in `main()`. +Both the builtin joystick library and the provided _KBD_ library provide an interface to the hardware, +albeit in different ways. +After initialization, the joystick is _polled_, +returning a `uint32_t` value. +While the KBD library defines values for each state that can be compared as a boolean, +the builtin library defines masks to read the direction as a bit, +also as a `uint32_t`. + +By relying on the default C99 boolean behaviour, +0 being _false_ and any other integer being _true_, +the joystick direction can be determined by masking the current joystick state with each mask, +which are defined alongside the joystick functions in the builtin library. +For example, if the joystick is pushed to the right, +the respective bit in the joystick _word_ will be set high. +When a logical _and_ is performed with the value and mask, +every bit other than the desired `JOYSTICK_RIGHT` bit will be 0. +Since the joystick is pushed right, this bit will be 1, +resulting in a non-zero value C will then treat as true. + +This is demonstrated in Figure 1, +where the state is fetched and used to set a variable with the current state, +and modify the LEDs on the board in a similar fashion. +The variable is later used to update the LCD screen. + + + +From this point, +extraneous code related to the ADC function was removed, +and any references, such as in `IRQ.c`, were commented out. + +# Appendix + +``` +/*---------------------------------------------------------------------------- + * Name: Blinky.c + * Purpose: LED Flasher + * Note(s): __USE_LCD - enable Output on LCD, uncomment #define in code to use + * for demo (NOT for analysis purposes) + *---------------------------------------------------------------------------- + * Copyright (c) 2008-2011 Keil - An ARM Company. + * Name: Anita Tino + *----------------------------------------------------------------------------*/ + +#include "Blinky.h" + +#include <stdio.h> + +#include "Board_Joystick.h" +#include "GLCD.h" +#include "LED.h" +#include "LPC17xx.h" + +#define __FI 1 /* Font index 16x24 */ +#define __USE_LCD 0 /* Uncomment to use the LCD */ + +// ITM Stimulus Port definitions for printf ////////////////// +#define ITM_Port8(n) (*((volatile unsigned char *)(0xE0000000 + 4 * n))) +#define ITM_Port16(n) (*((volatile unsigned short *)(0xE0000000 + 4 * n))) +#define ITM_Port32(n) (*((volatile unsigned long *)(0xE0000000 + 4 * n))) + +#define DEMCR (*((volatile unsigned long *)(0xE000EDFC))) +#define TRCENA 0x01000000 + +struct __FILE { + int handle; +}; +FILE __stdout; +FILE __stdin; + +int fputc(int ch, FILE *f) { + if (DEMCR & TRCENA) { + while (ITM_Port32(0) == 0); + ITM_Port8(0) = ch; + } + return (ch); +} + +/* Import external variables from IRQ.c file */ +extern uint8_t clock_ms; + +int main(void) { + LED_Init(); /* LED Initialization */ + Joystick_Initialize(); + +#ifdef __USE_LCD + GLCD_Init(); /* Initialize graphical LCD (if enabled */ + + GLCD_Clear(White); /* Clear graphical LCD display */ + GLCD_SetBackColor(Blue); + GLCD_SetTextColor(Yellow); + GLCD_DisplayString(0, 0, __FI, " COE718 Lab 1 "); + GLCD_SetTextColor(White); + GLCD_DisplayString(1, 0, __FI, " Blinky.c "); + GLCD_DisplayString(2, 0, __FI, " Try the joystick! "); + GLCD_SetBackColor(White); + GLCD_SetTextColor(Blue); + GLCD_DisplayString(6, 0, __FI, "Direction:"); +#endif + + // SystemCoreClockUpdate(); + SysTick_Config(SystemCoreClock / 100); + + const char *joystick = "NONE "; + while (1) { + const uint32_t state = Joystick_GetState(); + + if (state & JOYSTICK_LEFT) { + joystick = "LEFT "; + LED_Out(1); + } else if (state & JOYSTICK_RIGHT) { + joystick = "RIGHT"; + LED_Out(2); + } else if (state & JOYSTICK_DOWN) { + joystick = "DOWN "; + LED_Out(3); + } else if (state & JOYSTICK_UP) { + joystick = "UP "; + LED_Out(4); + } else if (state & JOYSTICK_CENTER) { + joystick = "PRESS"; + LED_Out(5); + } + +#ifdef __USE_LCD + GLCD_SetTextColor(Green); + GLCD_DisplayString(6, 11, __FI, (unsigned char *)joystick); +#endif + + /* Print message with AD value every 10 ms */ + if (clock_ms) { + clock_ms = 0; + + printf("Joystick: %s\r\n", joystick); + } + } +} + +``` |