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diff --git a/tinyusb/hw/bsp/msp430/family.c b/tinyusb/hw/bsp/msp430/family.c
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+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * This file is part of the TinyUSB stack.
+ */
+
+#include "bsp/board.h"
+#include "board.h"
+#include "msp430.h"
+
+//--------------------------------------------------------------------+
+// Forward USB interrupt events to TinyUSB IRQ Handler
+//--------------------------------------------------------------------+
+void __attribute__ ((interrupt(USB_UBM_VECTOR))) USB_UBM_ISR(void)
+{
+ tud_int_handler(0);
+}
+
+//--------------------------------------------------------------------+
+// MACRO TYPEDEF CONSTANT ENUM
+//--------------------------------------------------------------------+
+
+uint32_t cnt = 0;
+
+static void SystemClock_Config(void)
+{
+ WDTCTL = WDTPW + WDTHOLD; // Disable watchdog.
+
+ // Increase VCore to level 2- required for 16 MHz operation on this MCU.
+ PMMCTL0 = PMMPW + PMMCOREV_2;
+
+ UCSCTL3 = SELREF__XT2CLK; // FLL is fed by XT2.
+
+ // XT1 used for ACLK (default- not used in this demo)
+ P5SEL |= BIT4; // Required to enable XT1
+ // Loop until XT1 fault flag is cleared.
+ do
+ {
+ UCSCTL7 &= ~XT1LFOFFG;
+ }while(UCSCTL7 & XT1LFOFFG);
+
+ // XT2 is 4 MHz an external oscillator, use PLL to boost to 16 MHz.
+ P5SEL |= BIT2; // Required to enable XT2.
+ // Loop until XT2 fault flag is cleared
+ do
+ {
+ UCSCTL7 &= ~XT2OFFG;
+ }while(UCSCTL7 & XT2OFFG);
+
+ // Kickstart the DCO into the correct frequency range, otherwise a
+ // fault will occur.
+ // FIXME: DCORSEL_6 should work according to datasheet params, but generates
+ // a fault. I am not sure why it faults.
+ UCSCTL1 = DCORSEL_7;
+ UCSCTL2 = FLLD_2 + 3; // DCO freq = D * (N + 1) * (FLLREFCLK / n)
+ // DCOCLKDIV freq = (N + 1) * (FLLREFCLK / n)
+ // N = 3, D = 2, thus DCO freq = 32 MHz.
+
+ // MCLK configured for 16 MHz using XT2.
+ // SMCLK configured for 8 MHz using XT2.
+ UCSCTL4 |= SELM__DCOCLKDIV + SELS__DCOCLKDIV;
+ UCSCTL5 |= DIVM__16 + DIVS__2;
+
+ // Now wait till everything's stabilized.
+ do
+ {
+ UCSCTL7 &= ~(XT2OFFG + XT1LFOFFG + DCOFFG);
+ SFRIFG1 &= ~OFIFG;
+ }while(SFRIFG1 & OFIFG);
+
+ // Configure Timer A to use SMCLK as a source. Count 1000 ticks at 1 MHz.
+ TA0CCTL0 |= CCIE;
+ TA0CCR0 = 999; // 1000 ticks.
+ TA0CTL |= TASSEL_2 + ID_3 + MC__UP; // Use SMCLK, divide by 8, start timer.
+
+ // Initialize USB power and PLL.
+ USBKEYPID = USBKEY;
+
+ // VUSB enabled automatically.
+ // Wait two milliseconds to stabilize, per manual recommendation.
+ uint32_t ms_elapsed = board_millis();
+ do
+ {
+ while((board_millis() - ms_elapsed) < 2);
+ }while(!(USBPWRCTL & USBBGVBV));
+
+ // USB uses XT2 (4 MHz) directly. Enable the PLL.
+ USBPLLDIVB |= USBPLL_SETCLK_4_0;
+ USBPLLCTL |= (UPFDEN | UPLLEN);
+
+ // Wait until PLL locks. Check every 2ms, per manual.
+ ms_elapsed = board_millis();
+ do
+ {
+ USBPLLIR &= ~USBOOLIFG;
+ while((board_millis() - ms_elapsed) < 2);
+ }while(USBPLLIR & USBOOLIFG);
+
+ USBKEYPID = 0;
+}
+
+uint32_t wait = 0;
+
+void board_init(void)
+{
+ __bis_SR_register(GIE); // Enable interrupts.
+ SystemClock_Config();
+
+ // Enable basic I/O.
+ P1DIR |= LED_PIN; // LED output.
+ P1REN |= BUTTON_PIN; // Internal resistor enable.
+ P1OUT |= BUTTON_PIN; // Pullup.
+
+ // Enable the backchannel UART (115200)
+ P4DIR |= BIT5;
+ P4SEL |= (BIT5 | BIT4);
+
+ UCA1CTL1 |= (UCSSEL__SMCLK | UCSWRST); // Hold in reset, use SMCLK.
+ UCA1BRW = 4;
+ UCA1MCTL |= (UCBRF_3 | UCBRS_5 | UCOS16); // Overampling mode, 115200 baud.
+ // Copied from manual.
+ UCA1CTL1 &= ~UCSWRST;
+
+ // Set up USB pins.
+ USBKEYPID = USBKEY;
+ USBPHYCTL |= PUSEL; // Convert USB D+/D- pins to USB functionality.
+ USBKEYPID = 0;
+}
+
+//--------------------------------------------------------------------+
+// Board porting API
+//--------------------------------------------------------------------+
+
+void board_led_write(bool state)
+{
+ if(state)
+ {
+ LED_PORT |= LED_PIN;
+ }
+ else
+ {
+ LED_PORT &= ~LED_PIN;
+ }
+}
+
+uint32_t board_button_read(void)
+{
+ return ((P1IN & BIT1) >> 1) == BUTTON_STATE_ACTIVE;
+}
+
+int board_uart_read(uint8_t * buf, int len)
+{
+ for(int i = 0; i < len; i++)
+ {
+ // Wait until something to receive (cleared by reading buffer).
+ while(!(UCA1IFG & UCRXIFG));
+ buf[i] = UCA1RXBUF;
+ }
+
+ return len;
+}
+
+int board_uart_write(void const * buf, int len)
+{
+ const char * char_buf = (const char *) buf;
+
+ for(int i = 0; i < len; i++)
+ {
+ // Wait until TX buffer is empty (cleared by writing buffer).
+ while(!(UCA1IFG & UCTXIFG));
+ UCA1TXBUF = char_buf[i];
+ }
+
+ return len;
+}
+
+#if CFG_TUSB_OS == OPT_OS_NONE
+volatile uint32_t system_ticks = 0;
+void __attribute__ ((interrupt(TIMER0_A0_VECTOR))) TIMER0_A0_ISR (void)
+{
+ system_ticks++;
+ // TAxCCR0 CCIFG resets itself as soon as interrupt is invoked.
+}
+
+uint32_t board_millis(void)
+{
+ uint32_t systick_mirror;
+
+ // 32-bit update is not atomic on MSP430. We can read the bottom 16-bits,
+ // an interrupt occurs, updates _all_ 32 bits, and then we return a
+ // garbage value. And I've seen it happen!
+ TA0CCTL0 &= ~CCIE;
+ systick_mirror = system_ticks;
+ TA0CCTL0 |= CCIE;
+
+ return systick_mirror;
+}
+#endif