Software Overview
@CR1_SEND = #RES_4_BIT | ; set |
.endif
.if (EXTERNAL_CLOCK)
@CR0_SEND | ^= | #CLK_INTERNAL | ; | clear CLK_INTERNAL bit if one |
@CR0_SEND | = | #CLK_EXTERNAL | ; | set CLK_EXTERNAL mode |
.endif
.if (DIFF_INPUT_MODE)
@CR0_SEND | ^= | #SINGLE_END | ; | clear single ended input bit if one |
@CR0_SEND | = | #DIFFERENTIAL | ; | set differential input mode |
.endif
****************************************************************************
*Calibration:
*do a calibration of the input if chosen (the location of this instruction
*is only for an EVM test, in practice, the calibration procedure should
*be executed when the inputs are shorted to the correct voltage and after
*calibration, the analog signal is to apply before doing any further signal
*conversion)
*the calibration implementation is more or less inserted as an example
****************************************************************************
.if (IME_CALIBRATION)
call CALIBRAT_INTERNAL_MID_SCALE
.endif
.if (SME_CALIBRATION)
call CALIBRAT_SYSTEM_MID_SCALE
.endif |
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* ADC_INI: |
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* set ADC register CR0/CR1 |
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ADC_INI: |
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* write CR1: |
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port(ADC) = @CR1_SEND | ; Address decoder sets CS low, | ||||
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NOP | ; wait for tW(CSH)=50ns | ||||
* write CR0 |
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port(ADC) = @CR0_SEND | ; send CR0 value to the ADC | ||||
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STEP1: port(DEACTIVE) = @ZERO | ; deselect ADC (CS high) | ||||
STEP2: NOP | ; |
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NOP | ; |
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NOP | ; wait for t(SAMPLE1)=100ns | ||||
* initialize longer waitstates: |
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DP = #00000h | ; point to page zero |
@SWWSR = #07000h | ; one I/O wait states |
Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP | 77 |
