Added VBL-based waiting

ram2e.c

@@ -8,15 +8,32 @@
 #define true 1
 #define false 0
 
+
+#define VBL ((signed char*)0xC019)
+const uint8_t SPIN_HALFCYCLES = 3;
+const uint8_t SPIN_FRAMESPERCHAR = 4;
+
 #define PB0 ((char*)0xC061)
 #define PB1 ((char*)0xC062)
 static char read_applekey(void) { return (*PB0 | *PB1) & 0x80; }
 
-static void ram2e_cmd(char operation, char data) {
+char _cmd;
+char _arg;
+/* ram2e_cmd(...) issues a coded command+argument sequence to the RAM2E */
+static void ram2e_cmd(char cmd, char arg) {
 	// Load operation and data bytes into X and Y registers
 	// in preparation for command sequence
-	__asm__("ldx %o", operation);
+	_cmd = cmd;
-	__asm__("ldy %o", data);
+	_arg = arg;
+	__asm__("ldx %v", _cmd); // X = command
+	__asm__("ldy %v", _arg); // Y = argument
+
+	// First, reset command sequence just in case it,
+	// for some reason, has not timed out. (e.g. crazy fast accelerator?)
+	// Write 0 twice because command and argument steps always advance seq.
+	__asm__("lda #0");
+	__asm__("sta $C073");
+	__asm__("sta $C073");
 
 	// Command sequence
 	__asm__("lda #$FF");
@@ -31,44 +48,44 @@ static void ram2e_cmd(char operation, char data) {
 	__asm__("sta $C073");
 	__asm__("lda #$AD");
 	__asm__("sta $C073");
-	// Operation
+	// Command
 	__asm__("stx $C073");
-	// Data
+	// Argument
 	__asm__("sty $C073");
+
+	// Reset RAMWorks bank register just in case
+	__asm__("lda #0");
+	__asm__("sta $C073");
 }
+
+/* set_mask_temp(...) sends the "Set RAMWorks Capacity Mask" to the RAM2E */
 static void set_mask_temp(char mask) { ram2e_cmd(0xE0, mask); }
+
+/* ufm_bitbang(...) sends the "Set UFM Bitbang Outputs" to the RAM2E */
 static void ufm_bitbang(char bitbang) { ram2e_cmd(0xEA, bitbang); }
 
+/* ufm_program(...) sends the "UFM Program Once" command to the RAM2E */
+static void ufm_program() { ram2e_cmd(0xEF, 0x00); }
+
+/* ufm_erase(...) sends the "UFM Erase Once" command to the RAM2E */
+static void ufm_erase() { ram2e_cmd(0xEE, 0x00); }
+
+/* set_mask_temp(...) sends the "Set RAMWorks Capacity Mask" */
 static void set_nvm(char mask) {
 	int i;
-	// Shift mask into UFMD twice
+	// Shift mask OR'd with data register clock pulse trigger into UFMD twice
 	for (i = 0; i < 2; i++) {
-		char maskpart;
+		ufm_bitbang(0x80 | ((mask >> 1) & 0x40));
-
+		ufm_bitbang(0x80 | ((mask >> 0) & 0x40));
-		maskpart = 0x80 | ((mask >> 1) & 0x40);
+		ufm_bitbang(0x80 | ((mask << 1) & 0x40));
-		ufm_bitbang(maskpart);
+		ufm_bitbang(0x80 | ((mask << 2) & 0x40));
-
+		ufm_bitbang(0x80 | ((mask << 3) & 0x40));
-		maskpart = 0x80 | ((mask     ) & 0x40);
+		ufm_bitbang(0x80 | ((mask << 4) & 0x40));
-		ufm_bitbang(maskpart);
+		ufm_bitbang(0x80 | ((mask << 5) & 0x40));
-
+		ufm_bitbang(0x80 | ((mask << 6) & 0x40));
-		maskpart = 0x80 | ((mask << 1) & 0x40);
-		ufm_bitbang(maskpart);
-
-		maskpart = 0x80 | ((mask << 2) & 0x40);
-		ufm_bitbang(maskpart);
-
-		maskpart = 0x80 | ((mask << 3) & 0x40);
-		ufm_bitbang(maskpart);
-
-		maskpart = 0x80 | ((mask << 4) & 0x40);
-		ufm_bitbang(maskpart);
-
-		maskpart = 0x80 | ((mask << 5) & 0x40);
-		ufm_bitbang(maskpart);
-
-		maskpart = 0x80 | ((mask << 6) & 0x40);
-		ufm_bitbang(maskpart);
 	}
+	// Program UFM
+	ufm_program();
 }
 
 static void menu(void)
@@ -103,114 +120,131 @@ static void menu(void)
 }
 
 static void spin(uint8_t x, uint8_t y) { 
-	int i;
+	char i;
-	const uint8_t spin_big = 10;
-	const uint8_t spin_small = 150;
 
-	for (i = 0; i < spin_big; i++) {
+	// Sync to frame before starting
-		int j;
+	while (*VBL >= 0);
-		for (j = 0; j < spin_small; j++) {
+
-			__asm__("lda $C000");
+	// Wait and animate spinner.
+	// Spin_half
+	for (i = 0; i < SPIN_HALFCYCLES; i++) {
+		char j;
+		for (j = 0; j < 4; j++) {
+			char spinchar;
+			char k;
+
+			// Assign spinner char based on j
+			switch (j) {
+				case 0: spinchar = '\\'; break;
+				case 1: spinchar = '|'; break;
+				case 2: spinchar = '/'; break;
+				case 3: spinchar = '-'; break;
+				default: spinchar = '-'; break;
+			}
+
+			// Write it to screen
 			gotoxy(x, y);
-			__asm__("lda $C000");
+			putchar(spinchar);
-			cputs("-");
+
-			__asm__("lda $C000");
+			// Wait specificed number of frames
-		}
+			for (k = 0; k < SPIN_FRAMESPERCHAR; k++) {
-		for (j = 0; j < spin_small; j++) {
+				while (*VBL < 0);
-			__asm__("lda $C000");
+				while (*VBL >= 0);
-			gotoxy(x, y);
+			}
-			__asm__("lda $C000");
-			cputs("\\");
-			__asm__("lda $C000");
-		}
-		for (j = 0; j < spin_small; j++) {
-			__asm__("lda $C000");
-			gotoxy(x, y);
-			__asm__("lda $C000");
-			cputs("|");
-			__asm__("lda $C000");
-		}
-		for (j = 0; j < spin_small; j++) {
-			__asm__("lda $C000");
-			gotoxy(x, y);
-			__asm__("lda $C000");
-			cputs("/");
-			__asm__("lda $C000");
 		}
 	}
+
+	// Wait a frame when finished
+	while (*VBL < 0);
+	while (*VBL >= 0);
 }
 
 int main(void)
 {
-	char key;
 	char mask;
 	char nvm;
+	int reset_count;
 
+	// First clear screen
 	clrscr();
 
 	// Make sure we are running on an Apple IIe
 	if((get_ostype() & 0xF0) != APPLE_IIE) {
+		// If not on Apple IIe, show an error message and quit
 		gotoxy(0, 8);
 		cputs(" THIS PROGRAM REQUIRES AN APPLE IIE.");
 		gotoxy(0, 10);
 		cputs(" PRESS ANY KEY TO QUIT.");
-		cgetc();
+		cgetc(); // Wait for key
-		clrscr();
+		clrscr(); // Clear screen before quitting
 		return EXIT_SUCCESS;
 	}
 
 	// Show menu
 	menu();
 
-	// Get user choice
+	// Get user choice from menu
 	mask = 0;
 	nvm = 0;
+	reset_count = 0;
 	while (true) {
-		key = toupper(cgetc());
+		// Set capacity mask or quit according to keypress.
-
+		switch (toupper(cgetc())) {
-		// Set capacity mask or quit according to keypress
+			case 'Q' : {
-		if (key == 'Q') {
+				clrscr();
-			// Quit
+				return EXIT_SUCCESS;
-			clrscr();
+			}
-			return EXIT_SUCCESS;
+			case '1': mask = 0x00; break;
+			case '2': mask = 0x07; break;
+			case '3': mask = 0x0F; break;
+			case '4': mask = 0x3F; break;
+			case '5': mask = 0x7F; break;
+			case 'R': {
+				if (reset_count > 127) {
+					ufm_erase();
+					reset_count = 0;
+				} else { reset_count++; }
+			} default: continue;
 		}
-		else if (key == '1') { mask = 0x00; }
-		else if (key == '2') { mask = 0x07; }
-		else if (key == '3') { mask = 0x0F; }
-		else if (key == '4') { mask = 0x3F; }
-		else if (key == '5') { mask = 0x7F; }
-		else { continue; }
 
-		// Check if pressed with apple key
+		// Check if pressed with apple key.
+		// If so, save to nonvolatile memory.
 		if (read_applekey()) { nvm = true; }
 		break;
 	}
 
-	// Set capacity in volatile memory
+	// Set capacity in volatile memory.
 	set_mask_temp(mask);
 
+	// Clear screen in preparation to show saving or success message.
 	clrscr();
-	if (nvm) { // Save in NVM if requested
-		set_nvm(mask);
 
+	if (nvm) { // Save in NVM if requested.
+		// Show message about saving.
 		gotoxy(1, 8);
 		cputs("Saving RAM2E capacity setting.");
 		gotoxy(1, 9);
 		cputs("Do not turn off your Apple.");
 
+		// Save capacity in nonvolatile memory.
+		set_nvm(mask);
+
+		// Wait for >= 500ms on even the fastest systems.
 		spin(32, 8);
 
+		// Clear screen again.
 		clrscr();
 
 		gotoxy(1, 8);
 		cputs("RAM2E capacity saved successfully.");
-	} else { // Print success message
+	} else { // Print success message if not saving in NVM.
 		gotoxy(1, 8);
 		cputs("RAM2E capacity set successfully.");
 	}
-
 	gotoxy(1, 10);
 	cputs("Press any key to quit.");
+	gotoxy(1, 11);
+	cputs("You may also turn off your Apple.");
 	cgetc();
 
 	// Quit