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targets/TARGET_NXP/TARGET_LPC2460/analogout_api.c@178:c26431f84b0d, 2017-11-09 (annotated)
- Committer:
- amithy
- Date:
- Thu Nov 09 22:14:37 2017 +0000
- Revision:
- 178:c26431f84b0d
- Parent:
- 149:156823d33999
test export
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
<> | 144:ef7eb2e8f9f7 | 1 | /* mbed Microcontroller Library |
<> | 144:ef7eb2e8f9f7 | 2 | * Copyright (c) 2006-2015 ARM Limited |
<> | 144:ef7eb2e8f9f7 | 3 | * |
<> | 144:ef7eb2e8f9f7 | 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
<> | 144:ef7eb2e8f9f7 | 5 | * you may not use this file except in compliance with the License. |
<> | 144:ef7eb2e8f9f7 | 6 | * You may obtain a copy of the License at |
<> | 144:ef7eb2e8f9f7 | 7 | * |
<> | 144:ef7eb2e8f9f7 | 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
<> | 144:ef7eb2e8f9f7 | 9 | * |
<> | 144:ef7eb2e8f9f7 | 10 | * Unless required by applicable law or agreed to in writing, software |
<> | 144:ef7eb2e8f9f7 | 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
<> | 144:ef7eb2e8f9f7 | 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
<> | 144:ef7eb2e8f9f7 | 13 | * See the License for the specific language governing permissions and |
<> | 144:ef7eb2e8f9f7 | 14 | * limitations under the License. |
<> | 144:ef7eb2e8f9f7 | 15 | */ |
<> | 144:ef7eb2e8f9f7 | 16 | #include "mbed_assert.h" |
<> | 144:ef7eb2e8f9f7 | 17 | #include "analogout_api.h" |
<> | 144:ef7eb2e8f9f7 | 18 | #include "cmsis.h" |
<> | 144:ef7eb2e8f9f7 | 19 | #include "pinmap.h" |
<> | 144:ef7eb2e8f9f7 | 20 | |
<> | 144:ef7eb2e8f9f7 | 21 | static const PinMap PinMap_DAC[] = { |
<> | 144:ef7eb2e8f9f7 | 22 | {P0_26, DAC_0, 2}, |
<> | 144:ef7eb2e8f9f7 | 23 | {NC , NC , 0} |
<> | 144:ef7eb2e8f9f7 | 24 | }; |
<> | 144:ef7eb2e8f9f7 | 25 | |
<> | 144:ef7eb2e8f9f7 | 26 | void analogout_init(dac_t *obj, PinName pin) { |
<> | 144:ef7eb2e8f9f7 | 27 | obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC); |
<> | 144:ef7eb2e8f9f7 | 28 | MBED_ASSERT(obj->dac != (DACName)NC); |
<> | 144:ef7eb2e8f9f7 | 29 | |
<> | 144:ef7eb2e8f9f7 | 30 | // power is on by default, set DAC clk divider is /4 |
<> | 144:ef7eb2e8f9f7 | 31 | LPC_SC->PCLKSEL0 &= ~(0x3 << 22); |
<> | 144:ef7eb2e8f9f7 | 32 | |
<> | 144:ef7eb2e8f9f7 | 33 | // map out (must be done before accessing registers) |
<> | 144:ef7eb2e8f9f7 | 34 | pinmap_pinout(pin, PinMap_DAC); |
<> | 144:ef7eb2e8f9f7 | 35 | |
<> | 144:ef7eb2e8f9f7 | 36 | analogout_write_u16(obj, 0); |
<> | 144:ef7eb2e8f9f7 | 37 | } |
<> | 144:ef7eb2e8f9f7 | 38 | |
<> | 144:ef7eb2e8f9f7 | 39 | void analogout_free(dac_t *obj) {} |
<> | 144:ef7eb2e8f9f7 | 40 | |
<> | 144:ef7eb2e8f9f7 | 41 | static inline void dac_write(int value) { |
<> | 144:ef7eb2e8f9f7 | 42 | value &= 0x3FF; // 10-bit |
<> | 144:ef7eb2e8f9f7 | 43 | |
<> | 144:ef7eb2e8f9f7 | 44 | // Set the DAC output |
<> | 144:ef7eb2e8f9f7 | 45 | LPC_DAC->DACR = (0 << 16) // bias = 0 |
<> | 144:ef7eb2e8f9f7 | 46 | | (value << 6); |
<> | 144:ef7eb2e8f9f7 | 47 | } |
<> | 144:ef7eb2e8f9f7 | 48 | |
<> | 144:ef7eb2e8f9f7 | 49 | static inline int dac_read() { |
<> | 144:ef7eb2e8f9f7 | 50 | return (LPC_DAC->DACR >> 6) & 0x3FF; |
<> | 144:ef7eb2e8f9f7 | 51 | } |
<> | 144:ef7eb2e8f9f7 | 52 | |
<> | 144:ef7eb2e8f9f7 | 53 | void analogout_write(dac_t *obj, float value) { |
<> | 144:ef7eb2e8f9f7 | 54 | if (value < 0.0f) { |
<> | 144:ef7eb2e8f9f7 | 55 | dac_write(0); |
<> | 144:ef7eb2e8f9f7 | 56 | } else if (value > 1.0f) { |
<> | 144:ef7eb2e8f9f7 | 57 | dac_write(0x3FF); |
<> | 144:ef7eb2e8f9f7 | 58 | } else { |
<> | 144:ef7eb2e8f9f7 | 59 | dac_write(value * (float)0x3FF); |
<> | 144:ef7eb2e8f9f7 | 60 | } |
<> | 144:ef7eb2e8f9f7 | 61 | } |
<> | 144:ef7eb2e8f9f7 | 62 | |
<> | 144:ef7eb2e8f9f7 | 63 | void analogout_write_u16(dac_t *obj, uint16_t value) { |
<> | 144:ef7eb2e8f9f7 | 64 | dac_write(value >> 6); // 10-bit |
<> | 144:ef7eb2e8f9f7 | 65 | } |
<> | 144:ef7eb2e8f9f7 | 66 | |
<> | 144:ef7eb2e8f9f7 | 67 | float analogout_read(dac_t *obj) { |
<> | 144:ef7eb2e8f9f7 | 68 | uint32_t value = dac_read(); |
<> | 144:ef7eb2e8f9f7 | 69 | return (float)value * (1.0f / (float)0x3FF); |
<> | 144:ef7eb2e8f9f7 | 70 | } |
<> | 144:ef7eb2e8f9f7 | 71 | |
<> | 144:ef7eb2e8f9f7 | 72 | uint16_t analogout_read_u16(dac_t *obj) { |
<> | 144:ef7eb2e8f9f7 | 73 | uint32_t value = dac_read(); // 10-bit |
<> | 144:ef7eb2e8f9f7 | 74 | return (value << 6) | ((value >> 4) & 0x003F); |
<> | 144:ef7eb2e8f9f7 | 75 | } |