/*
- * Copyright (c) 2004, Technische Universitaet Berlin
+ * Copyright (c) 2006, Technische Universitaet Berlin
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
#define CHECK_ARGS
/*
- * The msp430adc12_channel_config_t encapsulates all relevant flags for
- * sampling a single ADC12 channel on a per-client basis. They are taken from
- * the following MSP430 registers: ADC12CTL0, ADC12CTL1, ADC12MCTLx and TACTL
- * of TimerA (if applicable) and named according to section "17.3 ADC12
- * Registers" of the "MSP430x1xx Family User's Guide",
- * http://focus.ti.com/lit/ug/slau049e/slau049e.pdf).
- *
- * .inch: ADC12 input channel (ADC12MCTLx register). An (external) input channel
- * maps to one of msp430's A0-A7 pins (see device specific data sheet).
+ * The msp430adc12_channel_config_t includes all relevant flags to configure
+ * the ADC12 for single channel conversions. They are contained in the following
+ * MSP430 registers: ADC12CTL0, ADC12CTL1, ADC12MCTLx and TACTL of TimerA (if
+ * applicable) and named according to section "17.3 ADC12 Registers" of the
+ * "MSP430x1xx Family User's Guide".
+ *
+ * **********************************
+ *
+ * .inch: ADC12 input channel (ADC12MCTLx register). An (external) input
+ * channel maps to one of msp430's A0-A7 pins (see device specific data sheet).
*
- * .sref: reference voltage (ADC12MCTLx register). If
- * REFERENCE_VREFplus_AVss or REFERENCE_VREFplus_VREFnegterm is chosen
- * AND the client wires to Msp430Adc12RefVoltAutoClientC (or
- * REF_VOLT_AUTO_CONFIGURE is defined and the client wires to
- * AdcReadClientC, AdcReadNowClientC or AdcReadStreamClientC) then the
- * reference voltage generator is automatically switched on to the
- * voltage level defined by the "ref2_5v" flag (see below) whenever the
- * client accesses the ADC12. Otherwise both flags are ignored.
+ * .sref: reference voltage (ADC12MCTLx register). If REFERENCE_VREFplus_AVss
+ * or REFERENCE_VREFplus_VREFnegterm is chosen AND the client wires to the
+ * Msp430Adc12ClientAutoRVGC or Msp430Adc12ClientAutoDMA_RVGC component then
+ * the reference voltage generator has automatically been enabled to the
+ * voltage level defined by the "ref2_5v" flag (see below) when the
+ * Resource.granted() event is signalled to the client. Otherwise this flag is
+ * ignored.
*
- * .ref2_5v: Reference generator voltage level (ADC12CTL0 register). See
- * explanation to "sref" flag.
+ * .ref2_5v: Reference generator voltage level (ADC12CTL0 register). See "sref"
+ * flag.
*
- * .adc12ssel: ADC12 clock source select for the sample-hold-time
- * (ADC12CTL1 register). In combination the "adc12ssel", "adc12div" and
- * "sht" define the sample-hold-time: "adc12ssel" defines the clock
- * source, "adc12div" defines the ADC12 clock divider and "sht" define
- * the time expressed in jiffies.
+ * .adc12ssel: ADC12 clock source select for the sample-hold-time (ADC12CTL1
+ * register). In combination the "adc12ssel", "adc12div" and "sht" define the
+ * sample-hold-time: "adc12ssel" defines the clock source, "adc12div" defines
+ * the ADC12 clock divider and "sht" define the time expressed in jiffies.
+ * (the sample-hold-time depends on the resistence of the attached sensor, and
+ * is calculated using to the formula in section 17.2.4 of the user guide)
*
* .adc12div: ADC12 clock divider (ADC12CTL1 register). See "adc12ssel".
*
* .sht: Sample-and-hold time (ADC12CTL1 register). See "adc12ssel".
*
- * .sampcon_ssel: In combination with "sampcon_id" and the "jiffies"
- * parameter in the Msp430Adc12SingleChannel interface commands the
- * "sampcon_ssel" defines the sampling rate (TASSEL in TACTL register,
- * TimerA). It is the clock source for the SAMPCON signal, which
- * triggers the actual sampling. It is ignored when
- * Msp430Adc12SingleChannel.getSingleData() is used or the "jiffies"
- * parameter is zero; otherwise the SAMPCON signal is sourced from
- * TimerA, so that the multiple conversion mode can be made with the
- * user defined sampling rate.
+ * .sampcon_ssel: Clock source for the sampling period (TASSEL for TimerA).
+ * When an ADC client specifies a non-zero "jiffies" parameter (passed in the
+ * relevant Msp430Adc12SingleChannel interface commands), the ADC
+ * implementation will automatically configure TimerA to be sourced from
+ * "sampcon_ssel" with an input divider of "sampcon_id". During the sampling
+ * process TimerA will then be used to trigger a conversion every "jiffies"
+ * clock ticks.
*
- * .sampcon_id: Input divider for "sampcon_ssel" (IDx in TACTL
- * register, TimerA). See "sampcon_ssel".
+ * .sampcon_id: Input divider for "sampcon_ssel" (IDx in TACTL register,
+ * TimerA). See "sampcon_ssel".
*
*
* **********************************
*
- * EXAMPLE: Assuming that SMCLK runs at 1 MHz the following command fills the
- * user buffer with 2000 conversion results sampled on channel A2 with a
- * sampling rate of 4000 Hz, i.e. the multipleDataReady() event is signalled
- * after 500 ms. Note that the sampling rate is defined by the combination of
- * SAMPCON_SOURCE_SMCLK, SAMPCON_CLOCK_DIV_1 and the "jiffies" parameter of
- * 250.
- *
- *
- * uint16_t buffer[2000];
- * msp430adc12_channel_config_t config = {
- * INPUT_CHANNEL_A2, REFERENCE_VREFplus_AVss, REFVOLT_LEVEL_1_5,
- * SHT_SOURCE_SMCLK, SHT_CLOCK_DIV_1, SAMPLE_HOLD_64_CYCLES,
- * SAMPCON_SOURCE_SMCLK, SAMPCON_CLOCK_DIV_1
- * };
- *
- * event void Resource.granted()
- * {
- * if (call SingleChannel.getMultipleData(&config, buffer, 2000, 250)
- * == SUCCESS)
- * {
- * // .. multipleDataReady() event will be signalled in 500ms
- * } else {
- * // check error
- * }
- * }
+ * EXAMPLE: Assuming that SMCLK runs at 1 MHz the following code snippet
+ * performs 2000 ADC conversions on channel A2 with a sampling period of 4000 Hz.
+ * The sampling period is defined by the combination of SAMPCON_SOURCE_SMCLK,
+ * SAMPCON_CLOCK_DIV_1 and a "jiffies" parameter of (1000000 / 4000) = 250.
+
+ #define NUM_SAMPLES 2000
+ uint16_t buffer[NUM_SAMPLES];
+
+ msp430adc12_channel_config_t config = {
+ INPUT_CHANNEL_A2, REFERENCE_VREFplus_AVss, REFVOLT_LEVEL_NONE,
+ SHT_SOURCE_SMCLK, SHT_CLOCK_DIV_1, SAMPLE_HOLD_64_CYCLES,
+ SAMPCON_SOURCE_SMCLK, SAMPCON_CLOCK_DIV_1
+ };
+
+ event void Boot.booted()
+ {
+ call Resource.request();
+ }
+
+ event void Resource.granted()
+ {
+ error_t result;
+ result = call SingleChannel.configureMultiple(&config, buffer, BUFFER_SIZE, 250);
+ if (result == SUCCESS)
+ call SingleChannel.getData();
+ }
+
+ async event uint16_t* SingleChannel.multipleDataReady(uint16_t *buf, uint16_t length)
+ {
+ // buffer contains conversion results
+ }
*/
// The unique string for accessing HAL2 via ReadStream
#define ADCC_READ_STREAM_SERVICE "AdcC.ReadStream.Client"
-
typedef struct
{
volatile unsigned
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