VGA/PCEmulator/PCEmulator.ino

A i8086 based IBM PC emulator (runs FreeDOS, MS-DOS, CPM86, Linux-ELK, Windows 3.0)

/*
  Created by Fabrizio Di Vittorio (fdivitto2013@gmail.com) - <http://www.fabgl.com>
  Copyright (c) 2019-2022 Fabrizio Di Vittorio.
  All rights reserved.
 
 
* Please contact fdivitto2013@gmail.com if you need a commercial license.
 
 
* This library and related software is available under GPL v3.
 
  FabGL is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.
 
  FabGL is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
 
  You should have received a copy of the GNU General Public License
  along with FabGL.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 
 /* Instructions:
 
    - to run this application you need an ESP32 with PSRAM installed and an SD-CARD slot (ie TTGO VGA32 v1.4 or FabGL Development Board with WROVER)
    - open this with Arduino and make sure PSRAM is DISABLED
    - partition scheme must be: Huge App
    - compile and upload the sketch
 
 */
 
 
#pragma message "This sketch requires Tools->Partition Scheme = Huge APP"
 
 
#include <memory>
 
#include "esp32-hal-psram.h"
extern "C" {
#include "esp_spiram.h"
}
#include "esp_sntp.h"
 
#include <Preferences.h>
#include <WiFi.h>
#include <HTTPClient.h>
 
#include "fabgl.h"
 
#include "mconf.h"
#include "machine.h"
 
 
 
using std::unique_ptr;
 
using fabgl::StringList;
using fabgl::imin;
using fabgl::imax;
 
 
 
Preferences   preferences;
InputBox      ibox;
Machine     * machine;
 
 
// noinit! Used to maintain datetime between reboots
__NOINIT_ATTR static timeval savedTimeValue;
 
 
static bool wifiConnected = false;
static bool downloadOK    = false;
 
 
// try to connected using saved parameters
bool tryToConnect()
{
  bool connected = WiFi.status() == WL_CONNECTED;
  if (!connected) {
    char SSID[32] = "";
    char psw[32]  = "";
    if (preferences.getString("SSID", SSID, sizeof(SSID)) && preferences.getString("WiFiPsw", psw, sizeof(psw))) {
      ibox.progressBox("", "Abort", true, 200, [&](fabgl::ProgressForm * form) {
        WiFi.begin(SSID, psw);
        for (int i = 0; i < 32 && WiFi.status() != WL_CONNECTED; ++i) {
          if (!form->update(i * 100 / 32, "Connecting to %s...", SSID))
            break;
          delay(500);
          if (i == 16)
            WiFi.reconnect();
        }
        connected = (WiFi.status() == WL_CONNECTED);
      });
      // show to user the connection state
      if (!connected) {
        WiFi.disconnect();
        ibox.message("", "WiFi Connection failed!");
      }
    }
  }
  return connected;
}
 
 
bool checkWiFi()
{
  wifiConnected = tryToConnect();
  if (!wifiConnected) {
 
    // configure WiFi?
    if (ibox.message("WiFi Configuration", "Configure WiFi?", "No", "Yes") == InputResult::Enter) {
 
      // repeat until connected or until user cancels
      do {
 
        // yes, scan for networks showing a progress dialog box
        int networksCount = 0;
        ibox.progressBox("", nullptr, false, 200, [&](fabgl::ProgressForm * form) {
          form->update(0, "Scanning WiFi networks...");
          networksCount = WiFi.scanNetworks();
        });
 
        // are there available WiFi?
        if (networksCount > 0) {
 
          // yes, show a selectable list
          StringList list;
          for (int i = 0; i < networksCount; ++i)
            list.appendFmt("%s (%d dBm)", WiFi.SSID(i).c_str(), WiFi.RSSI(i));
          int s = ibox.menu("WiFi Configuration", "Please select a WiFi network", &list);
 
          // user selected something?
          if (s > -1) {
            // yes, ask for WiFi password
            char psw[32] = "";
            if (ibox.textInput("WiFi Configuration", "Insert WiFi password", psw, 31, "Cancel", "OK", true) == InputResult::Enter) {
              // user pressed OK, connect to WiFi...
              preferences.putString("SSID", WiFi.SSID(s).c_str());
              preferences.putString("WiFiPsw", psw);
              wifiConnected = tryToConnect();
              // show to user the connection state
              if (wifiConnected)
                ibox.message("", "Connection succeeded!");
            } else
              break;
          } else
            break;
        } else {
          // there is no WiFi
          ibox.message("", "No WiFi network found!");
          break;
        }
        WiFi.scanDelete();
 
      } while (!wifiConnected);
 
    }
 
  }
 
  return wifiConnected;
}
 
 
// handle soft restart
void shutdownHandler()
{
  // save current datetime into Preferences
  gettimeofday(&savedTimeValue, nullptr);
}
 
 
void updateDateTime()
{
  // Set timezone
  setenv("TZ", "CET-1CEST,M3.5.0,M10.5.0/3", 1);
  tzset();
 
  // get datetime from savedTimeValue? (noinit section)
  if (esp_reset_reason() == ESP_RST_SW) {
    // adjust time taking account elapsed time since ESP32 started
    savedTimeValue.tv_usec += (int) esp_timer_get_time();
    savedTimeValue.tv_sec  += savedTimeValue.tv_usec / 1000000;
    savedTimeValue.tv_usec %= 1000000;
    settimeofday(&savedTimeValue, nullptr);
    return;
  }
 
  if (checkWiFi()) {
 
    // we need time right now
    ibox.progressBox("", nullptr, true, 200, [&](fabgl::ProgressForm * form) {
      sntp_setoperatingmode(SNTP_OPMODE_POLL);
      sntp_setservername(0, (char*)"pool.ntp.org");
      sntp_init();
      for (int i = 0; i < 12 && sntp_get_sync_status() != SNTP_SYNC_STATUS_COMPLETED; ++i) {
        form->update(i * 100 / 12, "Getting date-time from SNTP...");
        delay(500);
      }
      sntp_stop();
      ibox.setAutoOK(2);
      ibox.message("", "Date and Time updated. Restarting...");
      esp_restart();
    });
 
  } else {
 
    // set default time
    auto tm = (struct tm){ .tm_sec  = 0, .tm_min  = 0, .tm_hour = 8, .tm_mday = 14, .tm_mon  = 7, .tm_year = 84 };
    auto now = (timeval){ .tv_sec = mktime(&tm) };
    settimeofday(&now, nullptr);
 
  }
}
 
 
// download specified filename from URL
bool downloadURL(char const * URL, FILE * file)
{
  downloadOK = false;
 
  char const * filename = strrchr(URL, '/') + 1;
 
  ibox.progressBox("", "Abort", true, 380, [&](fabgl::ProgressForm * form) {
    form->update(0, "Preparing to download %s", filename);
    HTTPClient http;
    http.begin(URL);
    int httpCode = http.GET();
    if (httpCode == HTTP_CODE_OK) {
      if (file) {
        int tlen = http.getSize();
        int len = tlen;
        auto buf = (uint8_t*) SOC_EXTRAM_DATA_LOW; // use PSRAM as buffer
        WiFiClient * stream = http.getStreamPtr();
        int dsize = 0;
        while (http.connected() && (len > 0 || len == -1)) {
          size_t size = stream->available();
          if (size) {
            int c = stream->readBytes(buf, size);
            auto wr = fwrite(buf, 1, c, file);
            if (wr != c) {
              dsize = 0;
              break;  // writing failure!
            }
            dsize += c;
            if (len > 0)
              len -= c;
            if (!form->update((int64_t)dsize * 100 / tlen, "Downloading %s (%.2f / %.2f MB)", filename, (double)dsize / 1048576.0, tlen / 1048576.0))
              break;
          }
        }
        downloadOK = (len == 0 || (len == -1 && dsize > 0));
      }
    }
    http.end();
  });
 
  return downloadOK;
}
 
 
// return filename if successfully downloaded or already exist
char const * getDisk(char const * url)
{
  FileBrowser fb(SD_MOUNT_PATH);
 
  char const * filename = nullptr;
  if (url) {
    if (strncmp("://", url + 4, 3) == 0) {
      // this is actually an URL
      filename = strrchr(url, '/') + 1;
      if (filename && !fb.exists(filename, false)) {
        // disk doesn't exist, try to download
        if (!checkWiFi())
          return nullptr;
        auto file = fb.openFile(filename, "wb");
        bool success = downloadURL(url, file);
        fclose(file);
        if (!success) {
          fb.remove(filename);
          return nullptr;
        }
      }
    } else {
      // this is just a file
      if (fb.filePathExists(url))
        filename = url;
    }
  }
  return filename;
}
 
 
// user pressed SYSREQ (ALT + PRINTSCREEN)
void sysReqCallback()
{
  machine->graphicsAdapter()->enableVideo(false);
  ibox.begin(VGA_640x480_60Hz, 500, 400, 4);
 
  int s = ibox.menu("", "Select a command", "Restart (Boot Menu);Continue;Mount Disk");
  switch (s) {
 
    // Restart
    case 0:
      esp_restart();
      break;
 
    // Mount Disk
    case 2:
    {
      int s = ibox.menu("", "Select Drive", "Floppy A (fd0);Floppy B (fd1)");
      if (s > -1) {
        constexpr int MAXNAMELEN = 256;
        unique_ptr<char[]> dir(new char[MAXNAMELEN + 1] { '/', 'S', 'D', 0 } );
        unique_ptr<char[]> filename(new char[MAXNAMELEN + 1] { 0 } );
        if (machine->diskFilename(s))
          strcpy(filename.get(), machine->diskFilename(s));
        if (ibox.fileSelector("Select Disk Image", "Image Filename", dir.get(), MAXNAMELEN, filename.get(), MAXNAMELEN) == InputResult::Enter) {
          machine->setDriveImage(s, filename.get());
        }
      }
      break;
    }
 
    // Continue
    default:
      break;
  }
 
  ibox.end();
  PS2Controller::keyboard()->enableVirtualKeys(false, false); // don't use virtual keys
  machine->graphicsAdapter()->enableVideo(true);
}
 
 
void setup()
{
  Serial.begin(115200); delay(500); printf("\n\n\nReset\n\n");// DEBUG ONLY
 
 
  disableCore0WDT();
  delay(100); // experienced crashes without this delay!
  disableCore1WDT();
 
  preferences.begin("PCEmulator", false);
 
  // uncomment to clear preferences
  //preferences.clear();
  
  // save some space reducing UI queue
  fabgl::BitmappedDisplayController::queueSize = 128;
 
  ibox.begin(VGA_640x480_60Hz, 500, 400, 4);
  ibox.setBackgroundColor(RGB888(0, 0, 0));
 
  ibox.onPaint = [&](Canvas * canvas) { drawInfo(canvas); };
 
  // we need PSRAM for this app, but we will handle it manually, so please DO NOT enable PSRAM on your development env
  #ifdef BOARD_HAS_PSRAM
  ibox.message("Warning!", "Please disable PSRAM to improve performance!");
  #endif
 
  // note: we use just 2MB of PSRAM so the infamous PSRAM bug should not happen. But to avoid gcc compiler hack (-mfix-esp32-psram-cache-issue)
  // we enable PSRAM at runtime, otherwise the hack slows down CPU too much (PSRAM_HACK is no more required).
  if (esp_spiram_init() != ESP_OK)
    ibox.message("Error!", "This app requires a board with PSRAM!", nullptr, nullptr);
 
  #ifndef BOARD_HAS_PSRAM
  esp_spiram_init_cache();
  #endif
 
  if (!FileBrowser::mountSDCard(false, SD_MOUNT_PATH, 8))   // @TODO: reduce to 4?
    ibox.message("Error!", "This app requires a SD-CARD!", nullptr, nullptr);
 
  // uncomment to format SD!
  //FileBrowser::format(fabgl::DriveType::SDCard, 0);
 
  esp_register_shutdown_handler(shutdownHandler);
 
  updateDateTime();
 
  // machine configurations
  MachineConf mconf;
 
  // show a list of machine configurations
 
  ibox.setAutoOK(6);
  int idx = preferences.getInt("dconf", 0);
 
  for (bool showDialog = true; showDialog; ) {
 
    loadMachineConfiguration(&mconf);
 
    StringList dconfs;
    for (auto conf = mconf.getFirstItem(); conf; conf = conf->next)
      dconfs.append(conf->desc);
    dconfs.select(idx, true);
 
    ibox.setupButton(0, "Browse Files");
    ibox.setupButton(1, "Options", "Edit;New;Remove", 52);
    auto r = ibox.select("Machine Configurations", "Please select a machine configuration", &dconfs, nullptr, "Run");
 
    idx = dconfs.getFirstSelected();
 
    switch (r) {
      case InputResult::ButtonExt0:
        // Browse Files
        ibox.folderBrowser("Browse Files", SD_MOUNT_PATH);
        break;
      case InputResult::ButtonExt1:
        // Options
        switch (ibox.selectedSubItem()) {
          // Edit
          case 0:
            editConfigDialog(&ibox, &mconf, idx);
            break;
          // New
          case 1:
            newConfigDialog(&ibox, &mconf, idx);
            break;
          // Remove
          case 2:
            delConfigDialog(&ibox, &mconf, idx);
            break;
        };
        break;
      case InputResult::Enter:
        // Run
        showDialog = false;
        break;
      default:
        break;
    }
 
    // next selection will not have timeout
    ibox.setAutoOK(0);
  }
 
  idx = imax(idx, 0);
  preferences.putInt("dconf", idx);
 
  // setup selected configuration
  auto conf = mconf.getItem(idx);
 
  char const * diskFilename[DISKCOUNT];
  downloadOK = true;
  for (int i = 0; i < DISKCOUNT && downloadOK; ++i)
    diskFilename[i] = getDisk(conf->disk[i]);
 
  if (!downloadOK || (!diskFilename[0] && !diskFilename[2])) {
    // unable to get boot disks
    ibox.message("Error!", "Unable to get system disks!");
    esp_restart();
  }
 
  if (wifiConnected) {
    // disk downloaded from the Internet, need to reboot to fully disable wifi
    ibox.setAutoOK(2);
    ibox.message("", "Disks downloaded. Restarting...");
    esp_restart();
  }
 
  ibox.end();
 
  machine = new Machine;
 
  machine->setBaseDirectory(SD_MOUNT_PATH);
  for (int i = 0; i < DISKCOUNT; ++i)
    machine->setDriveImage(i, diskFilename[i], conf->cylinders[i], conf->heads[i], conf->sectors[i]);
 
  machine->setBootDrive(conf->bootDrive);
 
  /*
  printf("MALLOC_CAP_32BIT : %d bytes (largest %d bytes)\r\n", heap_caps_get_free_size(MALLOC_CAP_32BIT), heap_caps_get_largest_free_block(MALLOC_CAP_32BIT));
  printf("MALLOC_CAP_8BIT  : %d bytes (largest %d bytes)\r\n", heap_caps_get_free_size(MALLOC_CAP_8BIT), heap_caps_get_largest_free_block(MALLOC_CAP_8BIT));
  printf("MALLOC_CAP_DMA   : %d bytes (largest %d bytes)\r\n\n", heap_caps_get_free_size(MALLOC_CAP_DMA), heap_caps_get_largest_free_block(MALLOC_CAP_DMA));
 
  heap_caps_dump_all();
  */
 
  machine->setSysReqCallback(sysReqCallback);
 
  machine->run();
}
 
 
 
#if FABGLIB_VGAXCONTROLLER_PERFORMANCE_CHECK
namespace fabgl {
  extern volatile uint64_t s_vgapalctrlcycles;
}
using fabgl::s_vgapalctrlcycles;
#endif
 
 
 
void loop()
{
 
#if FABGLIB_VGAXCONTROLLER_PERFORMANCE_CHECK
  static uint32_t tcpu = 0, s1 = 0, count = 0;
  tcpu = machine->ticksCounter();
  s_vgapalctrlcycles = 0;
  s1 = fabgl::getCycleCount();
  delay(1000);
  printf("%d\tCPU: %d", count, machine->ticksCounter() - tcpu);
  printf("   Graph: %lld / %d   (%d%%)\n", s_vgapalctrlcycles, fabgl::getCycleCount() - s1, (int)((double)s_vgapalctrlcycles/240000000*100));
  ++count;
#else
 
  vTaskDelete(NULL);
 
#endif
}