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Diffstat (limited to 'peripherals/tsadcc/tsadcc.c')
| -rw-r--r-- | peripherals/tsadcc/tsadcc.c | 324 |
1 files changed, 324 insertions, 0 deletions
diff --git a/peripherals/tsadcc/tsadcc.c b/peripherals/tsadcc/tsadcc.c new file mode 100644 index 0000000..430ef8a --- /dev/null +++ b/peripherals/tsadcc/tsadcc.c @@ -0,0 +1,324 @@ +/* ----------------------------------------------------------------------------
+ * ATMEL Microcontroller Software Support
+ * ----------------------------------------------------------------------------
+ * Copyright (c) 2008, Atmel Corporation
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the disclaimer below.
+ *
+ * Atmel's name may not be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+ * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ----------------------------------------------------------------------------
+ */
+
+//------------------------------------------------------------------------------
+// Headers
+//------------------------------------------------------------------------------
+
+#include <board.h>
+
+#ifdef AT91C_BASE_TSADC
+
+#include <utility/trace.h>
+#include <utility/assert.h>
+
+//------------------------------------------------------------------------------
+// Local variables
+//------------------------------------------------------------------------------
+
+/// TSADC clock frequency in Hz.
+static unsigned int lAdcclk = 0;
+
+//------------------------------------------------------------------------------
+// Global functions
+//------------------------------------------------------------------------------
+
+//------------------------------------------------------------------------------
+/// Sets the operating mode of the TSADCC peripheral. The mode value can be
+/// one of the following:
+/// - AT91C_TSADC_TSAMOD_ADC_ONLY_MODE
+/// - AT91C_TSADC_TSAMOD_TS_ONLY_MODE
+/// \param mode Desired mode for the TSADCC.
+//------------------------------------------------------------------------------
+void TSADCC_SetOperatingMode(unsigned int mode)
+{
+ SANITY_CHECK( (mode == AT91C_TSADC_TSAMOD_ADC_ONLY_MODE)
+ | (mode == AT91C_TSADC_TSAMOD_TS_ONLY_MODE));
+
+ AT91C_BASE_TSADC->TSADC_MR = (AT91C_BASE_TSADC->TSADC_MR
+ & ~AT91C_TSADC_TSAMOD)
+ | mode;
+}
+
+//------------------------------------------------------------------------------
+/// Enables or disables the low resolution precision on the TSADC.
+/// \param enable If true, low resolution (8 bit) is used; otherwise the TSADC
+/// will use a 10-bit resolution.
+//------------------------------------------------------------------------------
+void TSADCC_SetLowResolution(unsigned char enable)
+{
+ if (enable) {
+
+ AT91C_BASE_TSADC->TSADC_MR |= AT91C_TSADC_LOWRES;
+ }
+ else {
+
+ AT91C_BASE_TSADC->TSADC_MR &= ~AT91C_TSADC_LOWRES;
+ }
+}
+
+//------------------------------------------------------------------------------
+/// Enables or disable SLEEP mode on the TSADC.
+/// \param enable If true, the TSADC is put into sleep mode; in normal mode
+/// otherwise.
+//------------------------------------------------------------------------------
+void TSADCC_SetSleepMode(unsigned char enable)
+{
+ if (enable) {
+
+ AT91C_BASE_TSADC->TSADC_MR |= AT91C_TSADC_SLEEP;
+ }
+ else {
+
+ AT91C_BASE_TSADC->TSADC_MR &= ~AT91C_TSADC_SLEEP;
+ }
+}
+
+//------------------------------------------------------------------------------
+/// Enables or disables pen detection on the TSADC.
+/// \param enable If true, pen detection is enabled; otherwise it is disabled.
+//------------------------------------------------------------------------------
+void TSADCC_SetPenDetect(unsigned char enable)
+{
+ if (enable) {
+
+ AT91C_BASE_TSADC->TSADC_MR |= AT91C_TSADC_PENDET;
+ }
+ else {
+
+ AT91C_BASE_TSADC->TSADC_MR &= ~AT91C_TSADC_PENDET;
+ }
+}
+
+//------------------------------------------------------------------------------
+/// Sets the TSADC clock to the desired frequency. The prescaler is calculated
+/// by this function so the resulting frequency is equal or inferior to the
+/// desired one.
+/// \param adcclk Desired ADC clock frequency in Hz.
+/// \param mck Master clock frequency in Hz.
+//------------------------------------------------------------------------------
+void TSADCC_SetAdcFrequency(unsigned int adcclk, unsigned int mck)
+{
+ unsigned int prescal;
+
+ // Formula for PRESCAL is:
+ // PRESCAL = (MCK / (2 * ADCCLK)) + 1
+ // First, we do the division, multiplied by 10 to get higher precision
+ // If the last digit is not zero, we round up to avoid generating a higher
+ // than required frequency.
+ prescal = (mck * 5) / adcclk;
+ if ((prescal % 10) > 0) {
+
+ prescal = (prescal / 10);
+ }
+ else {
+
+ SANITY_CHECK((prescal / 10) != 0);
+ prescal = (prescal / 10) - 1;
+ }
+ SANITY_CHECK(((prescal << 8) & ~AT91C_TSADC_PRESCAL) == 0);
+
+ AT91C_BASE_TSADC->TSADC_MR = ( AT91C_BASE_TSADC->TSADC_MR
+ & ~AT91C_TSADC_PRESCAL)
+ | (prescal << 8);
+
+ // Save clock frequency for further timing calculations
+ lAdcclk = adcclk;
+}
+
+//------------------------------------------------------------------------------
+/// Sets the TSADC startup time. This function relies on the ADCCLK frequency
+/// that has been set using TSADCC_SetAdcFrequency(), so it must have been
+/// called first.
+/// \param time Startup time in µseconds.
+//------------------------------------------------------------------------------
+void TSADCC_SetStartupTime(unsigned int time)
+{
+ unsigned int startup;
+
+ SANITY_CHECK(lAdcclk != 0);
+
+ // Formula for STARTUP is:
+ // STARTUP = (time x ADCCLK) / (1000000 x 8) - 1
+ // Division multiplied by 10 for higher precision
+ startup = (time * lAdcclk) / (800000);
+ if ((startup % 10) > 0) {
+
+ startup /= 10;
+ }
+ else {
+
+ startup /= 10;
+ if (startup > 0) {
+
+ startup--;
+ }
+ }
+
+ SANITY_CHECK((startup & ~0x7F) == 0);
+ AT91C_BASE_TSADC->TSADC_MR = ( AT91C_BASE_TSADC->TSADC_MR
+ & ~AT91C_TSADC_STARTUP)
+ | (startup << 16);
+}
+
+//------------------------------------------------------------------------------
+/// Sets the TSADC track and hold time. This function relies on the ADCCLK
+/// frequency that has been set with TSADCC_SetAdcFrequency(), to it must be
+/// called first.
+/// This function also sets the track and hold time in the TSADC_TSR register.
+/// \param time Track and hold time in nanoseconds.
+//------------------------------------------------------------------------------
+void TSADCC_SetTrackAndHoldTime(unsigned int time)
+{
+ unsigned int shtim;
+
+ SANITY_CHECK(lAdcclk != 0);
+
+ // Formula for SHTIM:
+ // SHTIM = (time x ADCCLK) / 1000000000 - 1
+ // Since 1 billion is close to the maximum value for an integer, we first
+ // divide ADCCLK by 1000 to avoid an overflow
+ shtim = (time * (lAdcclk / 1000)) / 100000;
+ if ((shtim % 10) > 0) {
+
+ shtim /= 10;
+ }
+ else {
+
+ shtim /= 10;
+ if (shtim > 0) shtim--;
+ }
+
+ SANITY_CHECK((shtim & ~0xF) == 0);
+ AT91C_BASE_TSADC->TSADC_MR = ( AT91C_BASE_TSADC->TSADC_MR
+ & ~AT91C_TSADC_SHTIM)
+ | (shtim << 24);
+ AT91C_BASE_TSADC->TSADC_TSR = shtim << 24;
+}
+
+//------------------------------------------------------------------------------
+/// Sets the TSADC debounce time. This function relies on the ADCCLK
+/// frequency that has been set with TSADCC_SetAdcFrequency(), to it must be
+/// called first.
+/// \param time Debounce time in nanoseconds (cannot be 0).
+//------------------------------------------------------------------------------
+void TSADCC_SetDebounceTime(unsigned int time)
+{
+ unsigned int divisor = 1000000000;
+ unsigned int clock = lAdcclk;
+ unsigned int pendbc = 0;
+ unsigned int targetValue;
+ unsigned int currentValue;
+
+ SANITY_CHECK(lAdcclk != 0);
+ SANITY_CHECK(time != 0);
+
+ // Divide time & ADCCLK first to avoid overflows
+ while ((divisor > 1) && ((time % 10) == 0)) {
+
+ time /= 10;
+ divisor /= 10;
+ }
+ while ((divisor > 1) && ((clock % 10) == 0)) {
+
+ clock /= 10;
+ divisor /= 10;
+ }
+
+ // Compute PENDBC value
+ targetValue = time * clock / divisor;
+ currentValue = 1;
+ while (currentValue < targetValue) {
+
+ pendbc++;
+ currentValue *= 2;
+ }
+
+ SANITY_CHECK((pendbc & ~0xF) == 0);
+ AT91C_BASE_TSADC->TSADC_MR = ( AT91C_BASE_TSADC->TSADC_MR
+ & ~AT91C_TSADC_PENDBC)
+ | (pendbc << 28);
+}
+
+//------------------------------------------------------------------------------
+/// Sets the trigger mode of the TSADCC to one of the following values:
+/// - AT91C_TSADC_TRGMOD_NO_TRIGGER
+/// - AT91C_TSADC_TRGMOD_EXTERNAL_TRIGGER_RE
+/// - AT91C_TSADC_TRGMOD_EXTERNAL_TRIGGER_FE
+/// - AT91C_TSADC_TRGMOD_EXTERNAL_TRIGGER_AE
+/// - AT91C_TSADC_TRGMOD_PENDET_TRIGGER
+/// - AT91C_TSADC_TRGMOD_PERIODIC_TRIGGER
+/// - AT91C_TSADC_TRGMOD_CONT_TRIGGER
+/// \param mode Trigger mode.
+//------------------------------------------------------------------------------
+void TSADCC_SetTriggerMode(unsigned int mode)
+{
+ SANITY_CHECK(((mode & ~AT91C_TSADC_TRGMOD) == 0)
+ | ((mode & AT91C_TSADC_TRGMOD) != 0x7));
+
+ AT91C_BASE_TSADC->TSADC_TRGR = (AT91C_BASE_TSADC->TSADC_TRGR
+ & ~AT91C_TSADC_TRGMOD)
+ | mode;
+}
+
+//------------------------------------------------------------------------------
+/// Sets the trigger period when using the TSADCC in periodic trigger mode.
+/// As usual, this function requires TSADCC_SetAdcFrequency() to be called
+/// before it.
+/// \param period Trigger period in nanoseconds.
+//------------------------------------------------------------------------------
+void TSADCC_SetTriggerPeriod(unsigned int period)
+{
+ unsigned int trgper;
+ unsigned int divisor = 100000000;
+
+ while ((period >= 10) && (divisor >= 10)) {
+
+ period /= 10;
+ divisor /= 10;
+ }
+
+ trgper = (period * lAdcclk) / divisor;
+ if ((trgper % 10) > 0) {
+
+ trgper /= 10;
+ }
+ else {
+
+ trgper /= 10;
+ if (trgper > 0) trgper--;
+ }
+
+ SANITY_CHECK((trgper & ~0xFFFF) == 0);
+ AT91C_BASE_TSADC->TSADC_TRGR = (AT91C_BASE_TSADC->TSADC_TRGR
+ & ~AT91C_TSADC_TRGPER)
+ | (trgper << 16);
+}
+
+#endif //#ifdef AT91C_BASE_TSADC
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