st7538 with PIC

[kartheek]

Posted on April 13, 2005 at 08:19

st7538 with PIC

[kartheek]

Posted on April 01, 2005 at 07:09

Hi Guys,

I am trying to integrate ST7538 with PICF8720

can someone please let me know few things on interfacing.

1. How many pins are required for interfacing st7538 to MCU (Min,Max)

2. What is zero crossing.

3. If anyne successfully integrated st7538 with PIC please let me know the configurations and pin connections.

4.what is the distance range of data sent ?

[sjo]

Posted on April 01, 2005 at 10:00

Have a look at an1714 -

http://www.st.com/stonline/books/pdf/docs/9546.pdf

datasheet also has info about connections

http://www.st.com/stonline/books/pdf/docs/9324.pdf

Regards

sjo

[alok2]

Posted on April 03, 2005 at 02:21

Hi Kartheek,

Readily available solution is available on ST72334. Why do you need to use PIC ?

Contact your local sales contact.

Alok

[krapf]

Posted on April 04, 2005 at 10:42

Hi Alok,

sometimes it is not only a matter of solution available, but also infrastructure for munufacturing the product with that device.

If our friend already has structure, tools, etc for PIC, why should he use another microcontroller?

Before I forget: I use 9 lines to communicate a PIC with the ST7538. I could use less lines, of course, the minimum is 6. But certain features I require in my system need these 9 lines.

Regards from BRASIL

PS: read all the comments about 7538 in the forum. There is some interesting tips here.

[onlyoneliveforever]

Posted on April 04, 2005 at 20:56

1 is the mininum ; One Wire

2 : I2C/SMBUS

3 : 3-Wires/SPI

if you use many pins you get more speed

but why using many Pin when the Microchip's Pic can be used to do something else while the ST7 do something more important with more free pin

[alok2]

Posted on April 05, 2005 at 02:58

Hi Krapf,

I agree with you that PIC is a forced choice if the tools are already available. but sometimes we start to work on a subject and spend time to develop something which is already available. the time to market is very important and extra cost to get the tools is less than the time spend on development. that's why it is wise to inform that a solution is available on which time can be spent for customisations..

Thanks a lot.

[krapf]

Posted on April 05, 2005 at 10:48

Hi Alok,

I am forced to agree with you. TIME TO MARKET IS KILLING.

:o :o :o :o

Cortex: how did you manage to use only one wire???

how do you say to the ST7538 to transmit and receive? how do you transmit and receive data in the same pin?

I got confused!

Rafael Krapf

BRASIL

[onlyoneliveforever]

Posted on April 05, 2005 at 16:07

u can use the interruptions.

fix a Normal State : ex : low

and when u want to communicated

change Input to Output and send the the data

the other side will be in input and will go to interruption code

i hope that you have understand the way

regards

[ This message was edited by: Cortex on 05-04-2005 19:40 ]

[krapf]

Posted on April 06, 2005 at 11:46

I understood,

but you still need at least two wires! :o

Remember the communication clock? (CLR/T) :-]

regards,

Rafael Krapf

BRASIL

[onlyoneliveforever]

Posted on April 07, 2005 at 21:21

no need

and why u use a OSC in MCU Then ??

u must send data and do some Delay() using Internal Osc (count the Cycles)

and the Receiver will Read and wait the same Delay