CFeed process

KSlibs/display.c

@@ -5,9 +5,14 @@
 #include <wiring.h>
 #define DelayMS(n) delay(n)
 
+/*
+Real important stuff:
+	Pins 0..2 of PORTG are Strobe, R/W, and Reg Select
+	Pins 0..3 of PORTA are D0..D3
+*/
 
 #define DISP_IN      {PORTA |= 0x0f; DDRA &= ~0x0f;}
-#define DISP_OUT     {DDRA |= 0x0f; }
+#define DISP_OUT     {DDRA |= 0x0f;}
 #define DISP_EN_HIGH {PORTG |= 0x01;}
 #define DISP_EN_LOW  {PORTG &= ~0x01;}
 #define DISP_READ    {PORTG |= 0x02;}
@@ -31,18 +36,18 @@ void Disp_Init() {
 unsigned char Disp_ReadSR() {
 	unsigned char highnib, lownib;
 
-	DISP_IN;
-	PORTG &= ~7;
-	DISP_IR;
-	DISP_READ;
+	DISP_IN;							// {PORTA |= 0x0f; DDRA &= ~0x0f;}	Make PORTA input, turn on pull-up resistors
+	PORTG &= ~7;						//									Turn off RW and RS
+	DISP_IR;							// {PORTG &= ~0x04;}				Turn off RS?
+	DISP_READ;							// {PORTG |= 0x02;}					Turn on RW
 
-	DISP_EN_HIGH; // read IR en
-	highnib = DISP_DATA_IN;
-	DISP_EN_LOW;
+	DISP_EN_HIGH; // read IR en			// {PORTG &= ~0x01;}				Strobe on
+	highnib = DISP_DATA_IN;				// (PINA & 0x0f)					Read nibble
+	DISP_EN_LOW;						// {PORTG &= ~0x01;}				Strobe off
 
-	DISP_EN_HIGH;
-	lownib = DISP_DATA_IN;
-	DISP_EN_LOW;
+	DISP_EN_HIGH;						// {PORTG &= ~0x01;}				Strobe on
+	lownib = DISP_DATA_IN;				// (PINA & 0x0f)					Read nibble
+	DISP_EN_LOW;						// {PORTG &= ~0x01;}				Strobe off
 
 	return (highnib << 4) + lownib;
 }
@@ -152,9 +157,9 @@ void Disp_Reset() {
 
 
 void Disp_Wait() {
-//	while (Disp_ReadSR() & 0x01) ;
-//delay(1);
-delayMicroseconds(75);
+//	while (Disp_ReadSR() & 0x40);
+//	delay(1);
+	delayMicroseconds(75);
 }
 
 
@@ -209,3 +214,9 @@ void Disp_CursOff() {
 	Disp_WriteIR(0x0c);  // display on, cursor off
 	Disp_Wait();
 }
+
+void Disp_Clear() {
+	Disp_WriteIR(0x01);    // display clear
+	//Disp_Wait();
+	DelayMS(2);
+}

KSlibs/display.h

@@ -15,6 +15,7 @@ void Disp_PutChar(char);
 void Disp_PutStr(char*);
 void Disp_CursOn();
 void Disp_CursOff();
+void Disp_Clear();
 
 
 

KSlibs/gpio.c

@@ -0,0 +1,27 @@
+#include <stdint.h>
+#include "gpio.h"
+
+#ifndef _BV
+#define _BV(bit) (1<<(bit))
+#endif
+
+// Set bit in DDR
+void gpio_set_ddr(gpio_s* p){
+	*(p->port - 1) |= _BV(p->pin);
+}
+// Clear bit in DDR
+void gpio_clr_ddr(gpio_s* p){
+	*(p->port - 1) &= 0xFF & ~_BV(p->pin);
+}
+// Set pin in PORT
+void gpio_set_pin(gpio_s* p){
+	*p->port |= _BV(p->pin);
+}
+// Clear pin in PORT
+void gpio_clr_pin(gpio_s* p){
+	*p->port &= 0xFF & ~_BV(p->pin);
+}
+// Get PIN value
+unsigned char gpio_get_pin(gpio_s* p){
+	return *(p->port - 2);
+}

KSlibs/gpio.h

@@ -0,0 +1,21 @@
+#ifndef GPIO_H
+#define GPIO_H
+typedef struct gpio {
+	volatile uint8_t *port;
+	unsigned char pin;
+} gpio_s;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+void gpio_set_ddr(gpio_s*);				// Set bit in DDR
+void gpio_clr_ddr(gpio_s*);				// Clear bit in DDR
+void gpio_set_pin(gpio_s*);				// Set pin in PORT
+void gpio_clr_pin(gpio_s*);				// Clear pin in PORT
+unsigned char gpio_get_pin(gpio_s*);	// Get PIN value
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // GPIO_H

KSlibs/intmath.c

@@ -0,0 +1,18 @@
+unsigned u_sublim (unsigned minuend, unsigned subtrahend, unsigned limit) {
+	unsigned x;
+	if (minuend < limit) return limit;			// Minuend must already be > limit
+	if (subtrahend > minuend) return limit;		// Avoid unsigned underflow (result < 0)
+	x = minuend - subtrahend;
+	if (x > limit) return x;
+	else return limit;
+}
+
+unsigned u_addlim (unsigned augend, unsigned addend, unsigned limit) {
+	unsigned x;
+	if (augend > limit) return limit;			// Augend must be < limit
+	if (addend > limit) return limit;			// Addend must be < limit
+	x = augend + addend;
+	if (x < addend) return limit;				// Overflow must have occurred (usually undefined behavior)
+	if (x < limit) return x;
+	else return limit;	
+}

KSlibs/intmath.h

@@ -0,0 +1,17 @@
+/*
+	intmath.h - integer math convenience functions
+*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Subtract and limit the result
+unsigned u_sublim (unsigned minuend, unsigned subtrahend, unsigned limit);
+
+// Add and limit the result
+unsigned u_addlim (unsigned augend, unsigned addend, unsigned limit);
+
+#ifdef __cplusplus
+}
+#endif

KSlibs/keypad.c

@@ -1,31 +1,28 @@
 #include <avr/io.h>
 
-
-
 void Kpd_Init() {
-	PORTA |= 0xf0;
-	DDRA &= ~0xf0;    // key0 - key3 are inputs with pullup
+	Kpd_Reset();
 }
 
-
-
 void Kpd_Reset() {
+	PORTA = 0xf0;	// Makse sure all key pins are set for input
+	DDRA = 0x0f;	// key0 - key3 are inputs with pullup
+
 }
 
 
-
-#define PBIT(n) (1 << (n))
-#define NBIT(n) (0x0f ^ PBIT(n))
+#define PBIT(n) (1 << (n))  // Set a single bit
+#define NBIT(n) (0x0f ^ PBIT(n))  // Clear a single bit, but keep the rest set (low nibble)
 #define SCAN(n) {PORTA |= NBIT(n); PORTA &= ~PBIT(n); DDRA &= ~NBIT(n); DDRA |= PBIT(n); }
-#define NOSCAN { PORTA |= 0x0f; DDRA &= ~0x0f; }
+#define NOSCAN { PORTA |= 0x0f; DDRA &= ~0x0f; }  // Set all bits in lower nibble; clear all bit in lower nibble of DDR
 
 
 int Kpd_Scan() {
 	unsigned char i, row;
-
+	Kpd_Reset();  // This fixes a bug where keys aren't read after the display is cleared
 	for (i=0; i<4; i++) {
 		SCAN(i);
-		row = ~((PINA & 0xf0) >> 4);
+		row = ~((PINA & 0xf0) >> 4);  // Read key bits from upper nibble and shift to lower nibble, then invert
 		if (row & 0x01) return i << 2;
 		if (row & 0x02) return (i << 2) + 1;
 		if (row & 0x04) return (i << 2) + 2;
@@ -42,7 +39,6 @@ int Kpd_Scan() {
 #undef NOSCAN
 
 
-
 int Kpd_GetKeyAsync() {
 	static int keylast = -1;