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[Bakari]

Dear Members,

Can any body show me the connection between PIC16F877 and ISD4002. I connected them and nothing is working. I have decided to start the troubleshooting with the connection. My connection was as follow (both have ICs DIP pachaging):

PIC16F877 ISD4002

Pin 18 Pin 28

Pin 23 Pin3

Pin 24 Pin 2

Pin 1 in ISD4002 is connected to ground because I need it always in slave mode. Pin 7 in PIC16F877 is connected to Vcc since I need it always in master mode.

Looking for any help.

Best regards,
Bakari

[mister_e]

To make things simple, you'll need to use SHIFTIN/SHIFTOUT in PBP. so it doesn't really matter the PIC I/O you use.

A while back i used a PIC16F628, Bellow is the hardware assignement i used.

    ' I/O Definition
    ' ===============
    '
    TRISA = %00110000    ' PORTA Output on :
                         '         PORTA<3:0> : LCD data 
                         '         PORTA<7:6> : LCD RS & E bit
                         '
                         ' PORTA Input on :
                         '         PORTA.4 : "ALT PLAY" Button
                         '         PORTA.5 : "PLAY" button    
                         '
    TRISB = %11110001    ' PORTB Output on : 
                         '         PORTB.1 : ISD4002 SS pin 
                         '         PORTB.2 : ISD4002 SCLK pin 
                         '         PORTB.3 : ISD4002 MOSI pin
                         '
                         ' PORTB Input on :
                         '         PORTB.0 : ISD4002 INT pin
                         '         PORTB.4 : ISD4002 MISO pin
                         '         PORTB.5 : ISD4002 RAC pin
                         '         PORTB.6 : "SETUP" button
                         '         PORTB.7 : "RECORD" button

Later to write to the ISD chip, i used

    ss = 0
    shiftout MOSI,SCLK,LSBFIRST,[ISDword\16]
    ss = 1

to read from

        ss=0
        shiftin miso,sclk,lsbpre,[isdpointer\16]
        ss=1

HTH

[Bakari]

Dear mister_e,

Thanks for your support. Could you please send me your code that used for controlling ISD4002. The one that includes the recording and playing back as well as the interrupt routine and the EOM one.

Waiting for your help, please

Best regards,
Bakari

[Bakari]

Dear Member,

Could you please tell me why you need to connect the interrupt pin from ISD4002 to the microcontroller while you can read the EOM or OVF flag from the MISO register? Also, why are you connecting the RAC pin? I think it’s possible to keep it floating. Finally, is it required to set a frequency for the SCLK pin from the microcontroller or they will communicate by default without setting any clock?

All my questions are based on my understanding. If there is any thing wrong please inform me. I am sorry for disturbing you. Thanks again for your help.

Best regards,
Bakari

[mister_e]

for the code... sorry i can't post this one. It's prop to a customer but i remind to see some example here... do a search and you'll find them

Yes you can skip the INT pin and read the EOM instead, same for RAC.

I used them to make things simple and retrieve the begin and end address of each message.

ISDs chips are close to be great, the only kind of bug if those 4002, is the pop sound at the begining and at the end... wich can be resolved in hardware... one reason of the RAC and INT.

You don't need to bother about the SCLK frequency... it will work. It's a synchronous communication, not like a simple SERIN/SEROUT where the baudrate is important.

[Bakari]

Dear mister_e,

I am sending this email for you to say thanks a lot for your great efforts (no other questions up to now)... Thaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa aanks.

Yours,
Bakari

[Agent36]

ISDs chips are close to be great, the only kind of bug if those 4002, is the pop sound at the begining and at the end... wich can be resolved in hardware... one reason of the RAC and INT.

Hi,
I am having problems with the pop sound can you let me know how you resolved it please? I found a data sheet from winbond giving a solution to the pop when recording, but not during the play back.

Thanks
Nick

[mister_e]

That's a pain, the only way i found was to monitor the address and use a extra mute circuit just before the EOF Interrupt.