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diff --git a/examples/baremetal/cy7c68013a/nes-gamepads/gpio.c b/examples/baremetal/cy7c68013a/nes-gamepads/gpio.c
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+/****************************************************************************
+**
+** Copyright (C) 2019 Denis Shienkov <denis.shienkov@gmail.com>
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of Qbs.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "core.h"
+#include "gpio.h"
+#include "hid.h"
+#include "regs.h"
+
+static WORD g_counter = 0;
+
+// We use this empirical value to make a GPIO polling
+// every ~10 msec (rough). It is a simplest way, because
+// instead we need to use a timers with interrupts callbacks.
+enum { POLLING_COUNTER = 580 };
+
+// Pins on the port A.
+enum gpio_pins {
+    GPIO_CLK_PIN = bmBIT0,
+    GPIO_DATA1_PIN = bmBIT2,
+    GPIO_DATA2_PIN = bmBIT4,
+    GPIO_LATCH_PIN = bmBIT6,
+};
+
+static struct {
+    const BYTE pin;
+    BYTE buttons;
+} g_reports[HID_REPORTS_COUNT] = {
+    {GPIO_DATA1_PIN, 0},
+    {GPIO_DATA2_PIN, 0}
+};
+
+// Pulse width around ~1 usec.
+static void gpio_latch_pulse(void)
+{
+    IOA |= GPIO_LATCH_PIN;
+    sync_delay();
+    sync_delay();
+    sync_delay();
+    IOA &= ~GPIO_LATCH_PIN;
+    sync_delay();
+}
+
+// Pulse width around ~1 usec.
+static void gpio_clk_pulse(void)
+{
+    IOA |= GPIO_CLK_PIN;
+    sync_delay();
+    sync_delay();
+    sync_delay();
+    IOA &= ~GPIO_CLK_PIN;
+    sync_delay();
+}
+
+static void gpio_reports_clean(void)
+{
+    BYTE index = 0;
+    for (index = 0; index < HID_REPORTS_COUNT; ++index)
+        g_reports[index].buttons = 0;
+}
+
+static void gpio_reports_send(void)
+{
+    BYTE index = 0;
+    for (index = 0; index < HID_REPORTS_COUNT; ++index)
+        hid_ep1_report_update(index, g_reports[index].buttons);
+}
+
+static void gpio_poll(void)
+{
+    BYTE pos = 0;
+
+    // Cleanup reports.
+    gpio_reports_clean();
+
+    // Send latch pulse.
+    gpio_latch_pulse();
+
+    for (pos = 0; pos < HID_REPORT_BITS_COUNT; ++pos) {
+        // TODO: Add some nops here?
+
+        BYTE index = 0;
+        for (index = 0; index < HID_REPORTS_COUNT; ++index) {
+            // Low state means that a button is pressed.
+            const BOOL v = (IOA & g_reports[index].pin) ? 0 : 1;
+            g_reports[index].buttons |= (v << pos);
+        }
+
+        // Send clock pulse.
+        gpio_clk_pulse();
+    }
+
+    gpio_reports_send();
+}
+
+void gpio_init(void)
+{
+    // Set interface to ports.
+    IFCONFIG = (IFCONFIG & (~bmIFCFG)) | bmIFPORTS;
+    sync_delay();
+
+    // Initialize the CLK and LATCH pins as output.
+    OEA = GPIO_CLK_PIN | GPIO_LATCH_PIN;
+    sync_delay();
+}
+
+void gpio_task(void)
+{
+    if (g_counter < POLLING_COUNTER) {
+        ++g_counter;
+    } else {
+        g_counter = 0;
+        gpio_poll();
+    }
+}