how to work with Bi-Directional data spi

[jaikumar]

Hi all,

I am trying to use this chip - RTC-4543 SA
Most SPI has a MISO MOSI or DI DO but this chip the data is bi-directional will the ccs spi driver support this chip or what changes do i have to do.

https://www.spezial.com/commercio/dateien/produktbeitraege/rtc-4543sa_sb.pdf

Thanks and Regards,
Jai

[temtronic]

I downloaded the applications manual and it's not really an SPI device. If you use Google you'll find a 'driver' for another micro , in C, that you could adapt for CCS C.
You'll need to read/write 52 bits of data though.
Epson is famous for this..I think it's based on nibbles rather then bytes.

hth
jay

[jaikumar]

So its a SERIAL-INTERFACE device not the Motorola SPI.

So the driver would be a software one. no hardware module in pic to perform

comm.

Thanks temtronic.

[temtronic]

YES ..NOT SPI, you have to create your own software driver...


jay

[Ttelmah]

As a quick comment, the standard #use rs232 driver may be able to do this!.
I don't know if the software serial driver supports software sync. You'd have to write a quick test to see. However if it does, you'd need to generate two streams, one for TX, and one for RX. So:

[Ttelmah]

Pull this manual, instead of the one you have:

<http://www.epsondevice.com/docs/qd/en/DownloadServlet?id=ID000500>

The supported baud rate is 128Hz, to 1.3MHz. Pretty much anything you want.

The format, could be generated by the hardware EUSART, as already mentioned. Being LSb first, it is not compatible with hardware SPI. It is basically synchronous serial, sending 6.5 bytes at a time. The hardware would have to do 7 bytes, but they are careful to tell you that extra clocks after the 52nd one are ignored, so 8bit hardware could be used.

It could also be generated by the software SPI routines, again using two streams, one for transmit, and one for receive.

[jaikumar]

Thanks Ttelmah.