analogout_api.h

00001 
00002 /** \addtogroup hal */
00003 /** @{*/
00004 /* mbed Microcontroller Library
00005  * Copyright (c) 2006-2013 ARM Limited
00006  * SPDX-License-Identifier: Apache-2.0
00007  *
00008  * Licensed under the Apache License, Version 2.0 (the "License");
00009  * you may not use this file except in compliance with the License.
00010  * You may obtain a copy of the License at
00011  *
00012  *     http://www.apache.org/licenses/LICENSE-2.0
00013  *
00014  * Unless required by applicable law or agreed to in writing, software
00015  * distributed under the License is distributed on an "AS IS" BASIS,
00016  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00017  * See the License for the specific language governing permissions and
00018  * limitations under the License.
00019  */
00020 #ifndef MBED_ANALOGOUT_API_H
00021 #define MBED_ANALOGOUT_API_H
00022 
00023 #include "device.h"
00024 #include "pinmap.h"
00025 
00026 #if DEVICE_ANALOGOUT
00027 
00028 #ifdef __cplusplus
00029 extern "C" {
00030 #endif
00031 
00032 /** Analogout hal structure. dac_s is declared in the target's hal
00033  */
00034 typedef struct dac_s dac_t;
00035 
00036 /**
00037  * \defgroup hal_analogout Analogout hal functions
00038  *
00039  * # Defined behaviour
00040  * * The function ::analogout_init initializes the dac_t control structure
00041  * * The function ::analogout_write sets the output voltage, specified as a percentage (float) in range [0.0 (GND), 1.0 (VCC)]
00042  * * The function ::analogout_write_u16 sets the output voltage, specified as unsigned 16-bit value [0 (GND), MAX_UINT16 (VCC)]
00043  * * The function ::analogout_read reads the current voltage value on the pin and returns a floating-point value representing the current voltage in range [0.0 (GND), 1.0 (VCC)]
00044  * * The function ::analogout_read_u16 reads the current voltage value on the pin and returns the output voltage, specified as unsigned 16-bit value [0 (GND), MAX_UINT16 (VCC)]
00045  * * The accuracy of the DAC is +/- 10%
00046  * * The DAC operations ::analogout_write, ::analogout_write_u16, ::analogout_read, ::analogout_read_u16 take less than 20us to complete
00047  * * The function ::analogout_free releases the analogout object
00048  *
00049  * # Undefined behaviour
00050  *
00051  * * ::analogout_init is called with invalid pin (which does not support analog output function)
00052  * * Calling other functions before ::analogout_init
00053  * @{
00054  */
00055 
00056 /**
00057  * \defgroup hal_analogin_tests Analogout hal tests
00058  * The Analogout HAL tests ensure driver conformance to defined behaviour.
00059  *
00060  * To run the Analogout hal tests use the command:
00061  *
00062  *     mbed test -t <toolchain> -m <target> -n tests-mbed_hal_fpga_ci_test_shield-analogout
00063  *
00064  */
00065 
00066 /** Initialize the analogout peripheral
00067  *
00068  * Configures the pin used by analogout.
00069  * @param obj The analogout object to initialize
00070  * @param pinmap pointer to structure which holds static pinmap
00071  */
00072 void analogout_init_direct(dac_t *obj, const PinMap *pinmap);
00073 
00074 /** Initialize the analogout peripheral
00075  *
00076  * Configures the pin used by analogout.
00077  * @param obj The analogout object to initialize
00078  * @param pin The analogout pin name
00079  */
00080 void analogout_init(dac_t *obj, PinName pin);
00081 
00082 /** Release the analogout object
00083  *
00084  * @param obj The analogout object
00085  */
00086 void analogout_free(dac_t *obj);
00087 
00088 /** Set the output voltage, specified as a percentage (float)
00089  *
00090  * @param obj The analogin object
00091  * @param value The floating-point output voltage to be set
00092  */
00093 void analogout_write(dac_t *obj, float value);
00094 
00095 /** Set the output voltage, specified as unsigned 16-bit
00096  *
00097  * @param obj The analogin object
00098  * @param value The unsigned 16-bit output voltage to be set
00099  */
00100 void analogout_write_u16(dac_t *obj, uint16_t value);
00101 
00102 /** Read the current voltage value on the pin
00103  *
00104  * @param obj The analogin object
00105  * @return A floating-point value representing the current voltage on the pin,
00106  *     measured as a percentage
00107  */
00108 float analogout_read(dac_t *obj);
00109 
00110 /** Read the current voltage value on the pin, as a normalized unsigned 16bit value
00111  *
00112  * @param obj The analogin object
00113  * @return An unsigned 16-bit value representing the current voltage on the pin
00114  */
00115 uint16_t analogout_read_u16(dac_t *obj);
00116 
00117 /** Get the pins that support analogout
00118  *
00119  * Return a PinMap array of pins that support analogout. The
00120  * array is terminated with {NC, NC, 0}.
00121  *
00122  * @return PinMap array
00123  */
00124 const PinMap *analogout_pinmap(void);
00125 
00126 /**@}*/
00127 
00128 #ifdef __cplusplus
00129 }
00130 #endif
00131 
00132 #endif
00133 
00134 #endif
00135 
00136 /** @}*/