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ISD1730 SPI Commands

Posted: Sat Jan 05, 2013 10:50 pm
by gggwww
Hello,
Trying to interface a 16F916 to an ISD Voice Chip using SPI commands.

The command structure for the PLAY Message op code is as follows:

BYTE 0 BYTE1
0x40 0x00

Looks like the Flowcode Send_Char only transmits 1 byte at a time I would need to do the following
SPI_INIT
SEND_CHAR 0x40 Play Opcode Byte
SEND_CHAR 0X00 Data Byte 1
SPI_UNINIT

Is the line SS held low between SPI_Init and SPI_UnInit regardless of how many SEND_CHAR's are in between? Some of the opcodes have up to 7 bytes and the chip expects SS to remain low during the time they are being sent.

Also, It's not clear in flowcode which pins are used for SS, SCLK and MOSI, MISO and how they are set

Hopefully this makes sense to someone

Thanks in advance !!

Re: ISD1730 SPI Commands

Posted: Fri Jan 11, 2013 4:33 pm
by Benj
Hello,

The CS pin is controlled by you, the init and uninit functions do not control the CS pin.

Most programs would simply initialise the SPI and then leave it this way.

The CS pins can be manually controlled using a output icon in single pin mode.

The hardware SPI specific pins are shown on the chip window - view - chip.

SCLK - SCK
MOSI - SDO
MISO - SDI

Example prog

Initialise SPI
output 0 to CS pin
SEND_CHAR 0x40 Play Opcode Byte
SEND_CHAR 0X00 Data Byte 1
output 1 to CS pin