HELP WITH PIC16F887 AND ISD1700 SPI PLEASE!!

[huytle1]

I am new to CCS and have looked through all the posts on SPI communication with the ISD4003 chip. All that information has helped me a great deal. However, I am trying to communicate with the ISD1700 and have no luck.

I am currently connecting the voice chip to a microchip serial analyzer and reading the spi ports with a logic analyzer. The pic serial analyzer is set up as the master and the voice a slave. I am putting in commands to see if the voice chip will communicate properly but get nothing!! I am following the datasheet by selecting CS low during data transfer and sending data but the chip doesn't record when I tell it to record.

If any one can help me or point me in the right direction of communicating through SPI that would be much appreciated. It is also my first time using SPI so I am pretty lost. hahaha.

If anyone can provide a step through of how to they connected there SPI and tested it that would be awesome. Thanks!

Current connection setup:

CS to CS
MISO to MOSI
MOSI to MISO
CLK to CLK

[PCM programmer]

Have you looked at the isd1700 design guide ? Here is the link:
http://www.atvoc.com/bbs/UploadFile/2007-7/20077259194287954.pdf
Based on the timing diagrams of the SPI interface on page 34, I would
say it uses SPI Mode 0. It's a little ambiguous, but Mode 0 is the best bet.
On page 71, it shows the maximum SCLK frequency is 1 MHz.

So, if you have found my previous posts on how to setup the SPI,
you should be able to set the mode and the SCLK divisor to meet
the requirements given above.

[ckielstra]

[PCM programmer]

But on page 34 of the Design Guide, it shows SCLK starting high, but
it ends low. That's why I said its ambiguous. (also, mode 4 ?)

[ckielstra]

[ckielstra]

For the SPI mode it would be worth a try to use the functions from the CCS supplied driver file ISD4003.c:
- init_isd
- write_isd
- read_isd

These functions implement a software based SPI driver sending the LSB first.

[huytle1]

THANKS FOR YOUR HELP EVERYONE!!!! i don't know what i would've done without everyones advice. it helped a ton!! thanks again.

[altipatlar006]

hi;
i am also interested in ISD1700 series and I want to share a working '8 bit code reverter' routine:

.
.
.
int8 received_data1,received_data2,reverted_data;
int8 buffer;
int flag,i;
void main()
{
while(1)
{
output_low(SS);
received_data1=spi_read(0x80);//reverted PU command-0x01-00000001
received_data2=spi_read(0x00);
output_high(SS);

for(flag=0;flag<8;flag++)
{
i=bit_test(received_data1,flag);
if (i==1)
bit_set(buffer,7-flag);
else
bit_clear(buffer,7-flag);
}
reverted_data=buffer;
//reverted_data[A2,A1,A0,INT,EOM,PU,FULL,CMD_ERR]
}
}

this routine will give you 0x04 which means PU is set 1 that device is powered and ready for SPI.

note:not the first loop but the second loop will give 0x04,this is -for my opinion-first status read operation returns wrong status info.
if you use a display with 1000 ms delay,you can monitor the outputs of the routine

[altipatlar006]

ckielstra said that:
In inactive state the clock polarity is high, so it is either Mode 3 or 4. Data is clocked in at the rising edge, that makes it Mode 4.

I think ckielstra mean mode 3 by Mode 4 and mode 2 by Mode 3.
and he/she is right because I used setup_spi(SPI_MASTER |SPI_H_TO_L | SPI_XMIT_L_TO_H|SPI_CLK_DIV_16 ) configuration and resulted code is given above.

[ckielstra]