Texas Instruments TLV1562 User Manual

Page 37

Software Overview

Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP

Start

Initialize DSP

Wait States, AR Pointer, IRQ Table, Data Memory, Serial Port

Initialize SPI

Active Transmitter, Use Frame Sync,

Generate External Clock

SAVE_INTO_MEMORY = 1

SAVE_INTO_MEMORY = 0

Initialize DSP Memory For Sample Store
AR7 Points to The First Store Location
AR0 Points to The Table End
ADCOUNT = Table Size (Number of Samples)

Initialize (Id) The Two ADC Registers
CR0 = CR0_SEND
CR1 = CR1_SEND

H/L Transition on INTO ?

Yes

INTO (External Interrupt)

Save Modified Register of

The IRQ Routine, if Not

Automatically Saved by The

DSP

(Not Required)

IME CALABRATION = 1

Calibrate Internal Midscale Error

IME CALABRATION = 0

SME CALABRATION = 1

Calibrate System Midscale Error

IME CALABRATION = 0

Start Sampling

Pull Down CSTART

Wait 100 ns

Stop Sampling and Start Conversion

Reset CSTART (Set Back High)

Table End Reached?

(AR7 = AR0 ?)

POLLING_DRIVEN =

Wait Until End of Conversion

Poll INTO Pin Until h/0 Transition Occurs

INTO_DRINEN = 1

Main Program

Stay in Idle Mode

NO_INTO_SIGNAL =

Wait Until End of Conversion

Wait For a Certain Time

INTO

SEND_OUT_PARALLEL = 1

Copy Last Sample to Parallel DAC

SEND_OUT_SERIAL = 1

SEND_OUT_SERIAL = 0

Copy Last Sample to Serial DAC

if Send Register is Empty

Start New Conversion

SAVE_INTO_MEMORY = 0

Store Sample Into Memory

Save Sample to AR7 – Pointed Location

Yes

Reset Actual Memory Pointer

AR& = First Memory Store Location

Start New Sampling

Pull Down CSTART

Read Sample

Stop Sampling and Start Conversion

Reset CSTART (Set Back High)

Figure 7. Flow Chart Mono Interrupt Driven Mode Using CSTART to Start Conversion