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Texas Instruments TLV1562 User Manual

Page 53

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Software Overview

47

Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP

CR0_SEND .usect ”.variabl”, 1 ; sent value to register CR0 of the ADC

CR1_SEND .usect ”.variabl”, 1 ; sent value to register CR1 of the ADC

ZERO .usect ”.variabl”, 1 ; the value zero to send a ”Zero Dummy”

ADSAMPLE .usect ”.variabl”, 1 ; last read sample from the ADC

* TLC5618 conversation

SERIAL_SEND .usect ”.variabl”, 1 ; serial output send word

* other

TEMP .usect ”.variabl”, 1 ; temporary variable, can be changed anywhere during
; the program

* Address Decoder constants:

CSTART .set 00001h ; activate A1 when CSTART is choosen

ADC .set 00002h ; activate A2 when TLV1562 is choosen

DAC1 .set 00003h ; activate A3 when DAC1 is choosen

DEACTIV .set 00000h ; deactivate the address lines A0, A1 and A2

* set timing mode (use od IRQ, or timer)

POLLING_DRV .set 00001h ; software polls the INT0 pin to wait, until conversion
is done

INT0_DRIVEN .set 00000h ; software uses Interrupt INT0 to organize conversion

NO_INT0_SIG .set 00000h ; INT0 signal not in use, interface is controlled with
timing solution

SAVE_INTO_MEMORY .set 00001h ; store the samples into DSP memory, defined in
”constants.asm”

SEND_OUT_SERIAL .set 00000h ; send the samples always to the serial DAC

SEND_OUT_PARALLEL .set 00001h ; update always the parallel DAC with the last sample
(DAC1)

R10BIT_RESOLUT .set 00001h ; use maximum resolution of 10-bit

R8BIT_RESOLUT .set 00000h ; use 8-bit resolution

R4BIT_RESOLUT .set 00000h ; use fastest mode (4-bit resolution)

INTERNAL_CLOCK .set 00001h ; use the internal clock of the ADC

EXTERNAL_CLOCK .set 00000h ; use the external clock of the ADC

AUTO_PWDN_ENABLE .set 00000h ; ADC goes into power reduced state after conversion

DIFF_INPUT_MODE .set 00001h ; use differential mode instead of single ended inputs

.sect ”.text”

_MAIN:

START:

INITIALIZATION:

* disable IRQ, sign extension mode, ini Stack

INTM = 1 ; disable IRQ

SXM = 0 ; no sign extension mode

; SP = #0280h ; initialize Stack pointer