ALS300 datasheet(43/66 Pages) ETC2

43 / 66 page

Avance Logic Inc.

ALS300

Appendix D : ESP/MPU401 Programming Guide

ESP Procedure:

ESP Read Data Procedure:

ESP_READ(return_byte)

If I/O read(ESP-RD-STATUS) bit 7 = 1 goto 2 else 1

Return_byte = I/O read(ESP-READ-DATA)

ESP Write Procedure:

ESP_WRITE(command/data)

If I/O read(ESP-WR-STATUS) bit7 = 0 goto 2 else 1

I/O write(ESP-COMMAND/DATA, command/data)

ESP Reset Procedure:

ESP_RESET( )

I/O write(ESP-RESET-PORT, 1), and wait 3 us

I/O write(ESP-RESET-PORT, 0)

ESP_READ(status), if status = AAh goto 4 else 3

End of reset

You can use ESP_RESET() procedure to immediately terminate the special DMA transfer.

Digitized Sound Transfer Method:

Direct Mode

ESP is programmed to do audio input/output on each command. All delay time is controlled by CPU

delay loop or timer interrupt. Only 8 bit mono input/output is supported.

Output:

a. ESP_WRITE(10h)

b. ESP_WRITE(next 8 bit mono PCM)

c. Wait until next sample time, goto a.

DMA Mode

2.1

Normal DMA Mode

ESP is programmed to make one transfer with a specified block size. At the end of transfer, the ESP will

generate an interrupt and wait for next command.

2.2

Continuous DMA Mode

ESP is programmed to make continuous transfer to/from CODEC. After each transfer of a specified

block size, ESP will generate an interrupt and continue the next transfer of the same block size after the

interrupt is acknlwoedged.

There are two ways to terminate continuous DMA mode transfer.

ALS300 Datasheet(PDF) 43 Page - List of Unclassifed Manufacturers