Added RAM2GS functionality

ram2gs.c

@@ -0,0 +1,173 @@
+#include <stdlib.h>
+#include <conio.h>
+#include <string.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <stdint.h>
+
+#include "util.h"
+#include "ram2gs_asm.h"
+
+static void ram2gs_erase() { ram2gs_cmd(0x28); }
+static void ram2gs_program() { ram2gs_cmd(0x24); }
+static void ram2gs_set4mb() { ram2gs_cmd(0x10); }
+static void ram2gs_set8mb() { ram2gs_cmd(0x11); }
+static void ram2gs_setnvm(char en8meg) {
+	char i;
+	// Clock in 0 to enable this setting entry
+	ram2gs_cmd(0x20);
+	ram2gs_cmd(0x22);
+
+	if (en8meg) {
+		// Clock in 1 to enable 8mb
+		ram2gs_cmd(0x21);
+		ram2gs_cmd(0x23);
+	} else {
+		// Clock in 0 to disable 8mb
+		ram2gs_cmd(0x20);
+		ram2gs_cmd(0x22);
+	}
+
+	// Clock in 14 dummy "1"s
+	for (i = 0; i < 14; i++) {
+		ram2gs_cmd(0x21);
+		ram2gs_cmd(0x23);
+	}
+
+	ram2gs_program();
+}
+
+static void menu(void)
+{
+	uint8_t bankcount = ram2gs_getsize();
+	gotoxy(5, 1);
+	cputs("-- RAM2GS Capacity Settings --");
+	gotoxy(4, 3);
+	printf("Current RAM2GS capacity: %d kB", bankcount * 64);
+
+	gotoxy(1, 6);
+	cputs("Select desired memory capacity:");
+
+	gotoxy(4, 8);
+	cputs("1. 4 megabytes");
+	gotoxy(4, 10);
+	cputs("2. 8 megabytes");
+
+	gotoxy(1, 18);
+	cputs("Capacity will be saved until power-off.");
+
+	gotoxy(1, 20);
+	cputs("To remember capacity setting in");
+	gotoxy(1, 21);
+	cputs("nonvolatile memory, press Apple+number.");
+
+	gotoxy(1, 23);
+	cputs("Press [Q] to quit without saving.");
+}
+
+int ram2gs_main(void)
+{
+	char en8meg;
+	char nvm;
+	int reset_count;
+
+	// Check for RAM2GS
+	#ifndef SKIP_RAM2GS_DETECT
+	if(!ram2gs_detect()) {
+		// If no RAM2GS, show an error message and quit
+		gotoxy(0, 8);
+		cputs(" No RAM2GS II detected.");
+		gotoxy(0, 10);
+		cputs(" Press any key to quit.");
+		cgetc(); // Wait for key
+		clrscr(); // Clear screen before quitting
+		return EXIT_SUCCESS;
+	}
+	#endif
+
+	menu(); // Print menu
+
+	// Get user choice from menu
+	en8meg = 0;
+	nvm = 0;
+	reset_count = 0;
+	while (true) {
+		// Set capacity or quit according to keypress.
+		switch (toupper(cgetc() & 0x7F)) {
+			case 'Q' : {
+				clrscr();
+				return EXIT_SUCCESS;
+			}
+			case '!': nvm = true;
+			case '1': en8meg = 0; ram2gs_set4mb(); break;
+			case '@': nvm = true;
+			case '2': en8meg = 1; ram2gs_set8mb(); break;
+			case 'R': {
+				reset_count++;
+				if (reset_count >= 100) {
+					// Show message about saving.
+					clrscr(); // Clear screen
+					gotoxy(1, 8);
+					cputs("Resetting RAM2GS settings.");
+					gotoxy(1, 9);
+					cputs("Do not turn off your Apple.");
+
+					ram2gs_erase(); // Erase RAM2GS settings memory
+					ram2gs_set8mb(); // Enable 8 megabytes now
+
+					// Wait for >= 500ms on even the fastest systems.
+					spin(32, 8);
+					
+					// Show success message and quit
+					clrscr(); // Clear screen
+					gotoxy(1, 8);
+					cputs("RAM2GS settings reset successfully.");
+					goto end;
+				}
+			} default: continue;
+		}
+
+		// Check if pressed with apple key. If so, save to nonvolatile memory.
+		if (read_applekey()) { nvm = true; }
+		break;
+	}
+
+	// Clear screen in preparation to show saving or success message.
+	clrscr();
+
+	if (nvm) { // Save in NVM if requested.
+		// Show message about saving.
+		gotoxy(1, 8);
+		cputs("Saving RAM2GS capacity setting.");
+		gotoxy(1, 9);
+		cputs("Do not turn off your Apple.");
+		// Save capacity in nonvolatile memory.
+		ram2gs_setnvm(en8meg);
+		// Wait for >= 500ms on even the fastest systems.
+		spin(33, 8);
+		// Print success message
+		clrscr(); // Clear screen
+		gotoxy(1, 8);
+		cputs("RAM2GS capacity saved successfully.");
+	} else { // Print success message if not saving in NVM.
+		gotoxy(1, 8);
+		cputs("RAM2GS capacity set successfully.");
+	}
+
+	end:
+	if (nvm) { // Show end message for nonvolatile save
+		gotoxy(1, 10);
+		cputs("You may now turn off your Apple.");
+		gotoxy(1, 12);
+		cputs("You may also reset your Apple for");
+		gotoxy(1, 13);
+		cputs("the setting change to take effect.");
+	} else { // Show end message for volatile save
+		gotoxy(1, 10);
+		cputs("Please reset your Apple for");
+		gotoxy(1, 11);
+		cputs("the setting change to take effect.");
+	}
+	// Don't quit. Instead leave prompt asking user to reset.
+	while(1) { cgetc(); }
+}