diff options
Diffstat (limited to 'tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088/pwmout_api.c')
| -rw-r--r-- | tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088/pwmout_api.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088/pwmout_api.c b/tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088/pwmout_api.c new file mode 100644 index 0000000000..3f34e397f9 --- /dev/null +++ b/tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088/pwmout_api.c @@ -0,0 +1,189 @@ +/* mbed Microcontroller 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 "mbed_assert.h" +#include "pwmout_api.h" +#include "cmsis.h" +#include "pinmap.h" + +#define TCR_CNT_EN 0x00000001 +#define TCR_RESET 0x00000002 + +// PORT ID, PWM ID, Pin function +static const PinMap PinMap_PWM[] = { + {P1_2, PWM0_1, 3}, + {P1_3, PWM0_2, 3}, + {P1_5, PWM0_3, 3}, + {P1_6, PWM0_4, 3}, + {P1_7, PWM0_5, 3}, + {P1_11, PWM0_6, 3}, + {P1_18, PWM1_1, 2}, + {P1_20, PWM1_2, 2}, + {P1_21, PWM1_3, 2}, + {P1_23, PWM1_4, 2}, + {P1_24, PWM1_5, 2}, + {P1_26, PWM1_6, 2}, + {P2_0, PWM1_1, 1}, + {P2_1, PWM1_2, 1}, + {P2_2, PWM1_3, 1}, + {P2_3, PWM1_4, 1}, + {P2_4, PWM1_5, 1}, + {P2_5, PWM1_6, 1}, + {P3_16, PWM0_1, 2}, + {P3_17, PWM0_2, 2}, + {P3_18, PWM0_3, 2}, + {P3_19, PWM0_4, 2}, + {P3_20, PWM0_5, 2}, + {P3_21, PWM0_6, 2}, + {P3_24, PWM1_1, 2}, + {P3_25, PWM1_2, 2}, + {P3_26, PWM1_3, 2}, + {P3_27, PWM1_4, 2}, + {P3_28, PWM1_5, 2}, + {P3_29, PWM1_6, 2}, + {NC, NC, 0} +}; + +static const uint32_t PWM_mr_offset[7] = { + 0x18, 0x1C, 0x20, 0x24, 0x40, 0x44, 0x48 +}; + +#define TCR_PWM_EN 0x00000008 +static unsigned int pwm_clock_mhz; + +void pwmout_init(pwmout_t* obj, PinName pin) { + // determine the channel + PWMName pwm = (PWMName)pinmap_peripheral(pin, PinMap_PWM); + MBED_ASSERT(pwm != (PWMName)NC); + + obj->channel = pwm; + obj->pwm = LPC_PWM0; + + if (obj->channel > 6) { // PWM1 is used if pwm > 6 + obj->channel -= 6; + obj->pwm = LPC_PWM1; + } + + obj->MR = (__IO uint32_t *)((uint32_t)obj->pwm + PWM_mr_offset[obj->channel]); + + // ensure the power is on + if (obj->pwm == LPC_PWM0) { + LPC_SC->PCONP |= 1 << 5; + } else { + LPC_SC->PCONP |= 1 << 6; + } + + obj->pwm->PR = 0; // no pre-scale + + // ensure single PWM mode + obj->pwm->MCR = 1 << 1; // reset TC on match 0 + + // enable the specific PWM output + obj->pwm->PCR |= 1 << (8 + obj->channel); + + pwm_clock_mhz = PeripheralClock / 1000000; + + // default to 20ms: standard for servos, and fine for e.g. brightness control + pwmout_period_ms(obj, 20); + pwmout_write (obj, 0); + + // Wire pinout + pinmap_pinout(pin, PinMap_PWM); +} + +void pwmout_free(pwmout_t* obj) { + // [TODO] +} + +void pwmout_write(pwmout_t* obj, float value) { + if (value < 0.0f) { + value = 0.0; + } else if (value > 1.0f) { + value = 1.0; + } + + // set channel match to percentage + uint32_t v = (uint32_t)((float)(obj->pwm->MR0) * value); + + // workaround for PWM1[1] - Never make it equal MR0, else we get 1 cycle dropout + if (v == obj->pwm->MR0) { + v++; + } + + *obj->MR = v; + + // accept on next period start + obj->pwm->LER |= 1 << obj->channel; +} + +float pwmout_read(pwmout_t* obj) { + float v = (float)(*obj->MR) / (float)(obj->pwm->MR0); + return (v > 1.0f) ? (1.0f) : (v); +} + +void pwmout_period(pwmout_t* obj, float seconds) { + pwmout_period_us(obj, seconds * 1000000.0f); +} + +void pwmout_period_ms(pwmout_t* obj, int ms) { + pwmout_period_us(obj, ms * 1000); +} + +// Set the PWM period, keeping the duty cycle the same. +void pwmout_period_us(pwmout_t* obj, int us) { + // calculate number of ticks + uint32_t ticks = pwm_clock_mhz * us; + + // set reset + obj->pwm->TCR = TCR_RESET; + + // set the global match register + obj->pwm->MR0 = ticks; + + // Scale the pulse width to preserve the duty ratio + if (obj->pwm->MR0 > 0) { + *obj->MR = (*obj->MR * ticks) / obj->pwm->MR0; + } + + // set the channel latch to update value at next period start + obj->pwm->LER |= 1 << 0; + + // enable counter and pwm, clear reset + obj->pwm->TCR = TCR_CNT_EN | TCR_PWM_EN; +} + +void pwmout_pulsewidth(pwmout_t* obj, float seconds) { + pwmout_pulsewidth_us(obj, seconds * 1000000.0f); +} + +void pwmout_pulsewidth_ms(pwmout_t* obj, int ms) { + pwmout_pulsewidth_us(obj, ms * 1000); +} + +void pwmout_pulsewidth_us(pwmout_t* obj, int us) { + // calculate number of ticks + uint32_t v = pwm_clock_mhz * us; + + // workaround for PWM1[1] - Never make it equal MR0, else we get 1 cycle dropout + if (v == obj->pwm->MR0) { + v++; + } + + // set the match register value + *obj->MR = v; + + // set the channel latch to update value at next period start + obj->pwm->LER |= 1 << obj->channel; +} |