I have ported my old project “pNesX” game console emulator to the nucleo.

Dependencies:   SDFileSystem mbed

Intro

I have ported my old project “pNesX” to the STM32 Nucleo. The pNesX is a NES emulator for the PlayStation that I have created 16 years ago!

Emulation part was almost without change, the sound part was newly added.

Parts

STM32 Nucleo F446RE
QVGA 2.2 TFT SPI (with the SD card slot)
Audio jack(TS or TRS)
USB Connector
Register 100k, 10k, 4.7k, 100
Capacitor 0.01uF, 2.2uF
Breadboard
Wires
Computer Speakers
USB GamePad

Wiring diagram

/media/uploads/beaglescout007/nucleo_ex06_emu.png

TFT J2Nucleo
VCC3V3
GNDGND
CSPB_5(D4)
ResetPA_10(D2) Pull Up(100k)
D/CPA_8(D7)
MOSIPA_7(D11)
SCKPA_5(D13)
LEDLED-100ohm-3V3
MISOPA_6(D12)
TFT J4Nucleo
SD_CSPA_9
SD_MOSIPB_15
SD_MISOPB_14
SD_SCKPB_13
AudioNucleo
TIPPA_4(A2)
USB con.Nucleo
GNDGND
+PA_12
-PA_11
5V5V

https://youtu.be/jL24IjT6LnI

Limitations

  • Since the rest of the RAM is about 50kbyte, maximum capacity of the game ROM is about 50kbyte.
  • The length of the file name up to 32 characters.
  • The number of files in the folder is up to 100.

Used Library

Revision:
0:3dac1f1bc9e0
diff -r 000000000000 -r 3dac1f1bc9e0 USBHost/USBHostGamepad.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/USBHost/USBHostGamepad.cpp	Sun Apr 03 07:45:29 2016 +0000
@@ -0,0 +1,119 @@
+/*
+ * mbed USBHost Gamepad driver sample
+ * Copyright (c) 2014 Yuuichi Akagawa
+ *
+ * modified from mbed USBHostMouse
+ *
+ * mbed USBHost Library
+ * Copyright (c) 2006-2013 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+ 
+#include "USBHostGamepad.h"
+//#if USBHOST_GAMEPAD
+
+USBHostGamepad::USBHostGamepad() {
+    host = USBHost::getHostInst();
+    init();
+}
+
+void USBHostGamepad::init() {
+    dev = NULL;
+    int_in = NULL;
+    dev_connected = false;
+    gamepad_device_found = false;
+    gamepad_intf = -1;
+}
+
+bool USBHostGamepad::connected() {
+    return dev_connected;
+}
+
+bool USBHostGamepad::connect() {
+    if (dev_connected) {
+        return true;
+    }
+
+    for (uint8_t i = 0; i < MAX_DEVICE_CONNECTED; i++) {
+        if ((dev = host->getDevice(i)) != NULL) {
+
+            if(host->enumerate(dev, this))
+                break;
+
+            if (gamepad_device_found) {
+
+                int_in = dev->getEndpoint(gamepad_intf, INTERRUPT_ENDPOINT, IN);
+                if (!int_in)
+                    break;
+
+                USB_INFO("New Gamepad/Joystick device: VID:%04x PID:%04x [dev: %p - intf: %d]", dev->getVid(), dev->getPid(), dev, gamepad_intf);
+#if DEBUG > 3
+                //Parse HID Report Descriptor
+                parseHidDescr();
+#endif
+                dev->setName("Gamepad", gamepad_intf);
+                host->registerDriver(dev, gamepad_intf, this, &USBHostGamepad::init);
+
+                int_in->attach(this, &USBHostGamepad::rxHandler);
+                rxSize = int_in->getSize();
+                if (rxSize > sizeof(report))
+                    rxSize = sizeof(report);
+                host->interruptRead(dev, int_in, report, rxSize, false);
+
+                dev_connected = true;
+                return true;
+            }
+        }
+    }
+    init();
+    return false;
+}
+
+void USBHostGamepad::rxHandler() {
+    if (dev)
+        host->interruptRead(dev, int_in, report, rxSize, false);
+        
+    /* modified 2016 Racoon */
+        
+}
+
+/*virtual*/ void USBHostGamepad::setVidPid(uint16_t vid, uint16_t pid)
+{
+    // we don't check VID/PID for gamepad driver
+}
+
+/*virtual*/ bool USBHostGamepad::parseInterface(uint8_t intf_nb, uint8_t intf_class, uint8_t intf_subclass, uint8_t intf_protocol) //Must return true if the interface should be parsed
+{
+    if ((gamepad_intf == -1) &&
+        (intf_class == HID_CLASS) &&
+        (intf_subclass == 0x00) &&
+        (intf_protocol == 0x00)) {
+        gamepad_intf = intf_nb;
+        return true;
+    }
+    return false;
+}
+
+/*virtual*/ bool USBHostGamepad::useEndpoint(uint8_t intf_nb, ENDPOINT_TYPE type, ENDPOINT_DIRECTION dir) //Must return true if the endpoint will be used
+{
+    if (intf_nb == gamepad_intf) {
+        if (type == INTERRUPT_ENDPOINT && dir == IN) {
+            gamepad_device_found = true;
+            return true;
+        }
+    }
+    return false;
+}
+
+