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Color Oled(SSD1331) connect to STMicroelectronics Nucleo-F466
Diff: mbed-os/targets/TARGET_Freescale/TARGET_KLXX/us_ticker.c
- Revision:
- 0:8fdf9a60065b
diff -r 000000000000 -r 8fdf9a60065b mbed-os/targets/TARGET_Freescale/TARGET_KLXX/us_ticker.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed-os/targets/TARGET_Freescale/TARGET_KLXX/us_ticker.c Wed Oct 10 00:33:53 2018 +0000 @@ -0,0 +1,230 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2018 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 <stddef.h> +#include "us_ticker_api.h" +#include "PeripheralNames.h" +#include "clk_freqs.h" + +const ticker_info_t* us_ticker_get_info() +{ + static const ticker_info_t info = { + 1000000, // 1 MHz + 32 // 32 bit counter + }; + return &info; +} + +static bool us_ticker_inited = false; + +static void pit_init(void); +static void lptmr_init(void); + + +void us_ticker_init(void) { + if (us_ticker_inited) { + /* calling init again should cancel current interrupt */ + us_ticker_disable_interrupt(); + return; + } + us_ticker_inited = true; + + pit_init(); + lptmr_init(); +} + +/****************************************************************************** + * Timer for us timing. + ******************************************************************************/ +static void pit_init(void) { + SIM->SCGC6 |= SIM_SCGC6_PIT_MASK; // Clock PIT + PIT->MCR = 0; // Enable PIT + + // Channel 1 + PIT->CHANNEL[1].LDVAL = 0xFFFFFFFF; + PIT->CHANNEL[1].TCTRL = PIT_TCTRL_CHN_MASK; // Chain to timer 0, disable Interrupts + PIT->CHANNEL[1].TCTRL |= PIT_TCTRL_TEN_MASK; // Start timer 1 + + // Use channel 0 as a prescaler for channel 1 + PIT->CHANNEL[0].LDVAL = (bus_frequency() + 500000) / 1000000 - 1; + PIT->CHANNEL[0].TCTRL = PIT_TCTRL_TEN_MASK; // Start timer 0, disable interrupts +} + +uint32_t us_ticker_read() { + // The PIT is a countdown timer + return ~(PIT->CHANNEL[1].CVAL); +} + +/****************************************************************************** + * Timer Event + * + * It schedules interrupts at given (32bit)us interval of time. + * It is implemented used the 16bit Low Power Timer that remains powered in all + * power modes. + ******************************************************************************/ +static void lptmr_isr(void); + +static void lptmr_init(void) { + uint32_t extosc; + + /* Clock the timer */ + SIM->SCGC5 |= SIM_SCGC5_LPTMR_MASK; + + /* Reset */ + LPTMR0->CSR = 0; + +#if defined(TARGET_KL43Z) + /* Set interrupt handler */ + NVIC_SetVector(LPTMR0_IRQn, (uint32_t)lptmr_isr); + NVIC_EnableIRQ(LPTMR0_IRQn); + + + MCG->C1 |= MCG_C1_IRCLKEN_MASK; + extosc = mcgirc_frequency(); +#else + /* Set interrupt handler */ + NVIC_SetVector(LPTimer_IRQn, (uint32_t)lptmr_isr); + NVIC_EnableIRQ(LPTimer_IRQn); + + /* Clock at (1)MHz -> (1)tick/us */ + /* Check if the external oscillator can be divided to 1MHz */ + extosc = extosc_frequency(); +#endif + if (extosc != 0) { //If external oscillator found + if (extosc % 1000000u == 0) { //If it is a multiple if 1MHz + extosc /= 1000000; + if (extosc == 1) { //1MHz, set timerprescaler in bypass mode + LPTMR0->PSR = LPTMR_PSR_PCS(3) | LPTMR_PSR_PBYP_MASK; + return; + } else { //See if we can divide it to 1MHz + uint32_t divider = 0; + extosc >>= 1; + while (1) { + if (extosc == 1) { + LPTMR0->PSR = LPTMR_PSR_PCS(3) | LPTMR_PSR_PRESCALE(divider); + return; + } + if (extosc % 2 != 0) //If we can't divide by two anymore + break; + divider++; + extosc >>= 1; + } + } + } + } +#if defined(TARGET_KL43Z) + //No suitable actual IRC oscillator clock -> Set it to (8MHz / divider) + MCG->SC &= ~MCG_SC_FCRDIV_MASK; + MCG->MC &= ~MCG->MC & MCG_MC_LIRC_DIV2_MASK; + LPTMR0->PSR = LPTMR_PSR_PCS(0) | LPTMR_PSR_PRESCALE(2); +#else + //No suitable external oscillator clock -> Use fast internal oscillator (4MHz / divider) + MCG->C1 |= MCG_C1_IRCLKEN_MASK; + MCG->C2 |= MCG_C2_IRCS_MASK; + LPTMR0->PSR = LPTMR_PSR_PCS(0); + switch (MCG->SC & MCG_SC_FCRDIV_MASK) { + case MCG_SC_FCRDIV(0): //4MHz + LPTMR0->PSR |= LPTMR_PSR_PRESCALE(1); + break; + case MCG_SC_FCRDIV(1): //2MHz + LPTMR0->PSR |= LPTMR_PSR_PRESCALE(0); + break; + default: //1MHz or anything else, in which case we put it on 1MHz + MCG->SC &= ~MCG_SC_FCRDIV_MASK; + MCG->SC |= MCG_SC_FCRDIV(2); + LPTMR0->PSR |= LPTMR_PSR_PBYP_MASK; + } +#endif +} + +void us_ticker_disable_interrupt(void) { + LPTMR0->CSR &= ~LPTMR_CSR_TIE_MASK; +} + +void us_ticker_clear_interrupt(void) { + // we already clear interrupt in lptmr_isr +} + +static uint32_t us_ticker_int_counter = 0; +static uint16_t us_ticker_int_remainder = 0; + +static void lptmr_set(unsigned short count) { + /* Reset */ + LPTMR0->CSR = 0; + + /* Set the compare register */ + LPTMR0->CMR = count; + + /* Enable interrupt */ + LPTMR0->CSR |= LPTMR_CSR_TIE_MASK; + + /* Start the timer */ + LPTMR0->CSR |= LPTMR_CSR_TEN_MASK; +} + +static void lptmr_isr(void) { + // write 1 to TCF to clear the LPT timer compare flag + LPTMR0->CSR |= LPTMR_CSR_TCF_MASK; + + if (us_ticker_int_counter > 0) { + lptmr_set(0xFFFF); + us_ticker_int_counter--; + + } else { + if (us_ticker_int_remainder > 0) { + lptmr_set(us_ticker_int_remainder); + us_ticker_int_remainder = 0; + + } else { + /* Stop the timer */ + LPTMR0->CSR &= ~LPTMR_CSR_TEN_MASK; + + // This function is going to disable the interrupts if there are + // no other events in the queue + us_ticker_irq_handler(); + } + } +} + +void us_ticker_set_interrupt(timestamp_t timestamp) { + uint32_t delta = timestamp - us_ticker_read(); + us_ticker_int_counter = (uint32_t)(delta >> 16); + us_ticker_int_remainder = (uint16_t)(0xFFFF & delta); + if (us_ticker_int_counter > 0) { + lptmr_set(0xFFFF); + us_ticker_int_counter--; + } else { + lptmr_set(us_ticker_int_remainder); + us_ticker_int_remainder = 0; + } +} + +void us_ticker_fire_interrupt(void) +{ + us_ticker_int_counter = 0; + us_ticker_int_remainder = 0; + +#if defined(TARGET_KL43Z) + NVIC_SetPendingIRQ(LPTMR0_IRQn); +#else + NVIC_SetPendingIRQ(LPTimer_IRQn); + +#endif +} + +void us_ticker_free(void) +{ + +}