[En-Nut-Discussion] NutI2cMasterTransceive() versus NutI2cMasterTransact()

[Uwe Bonnes]

>>>>> "Harald" == Harald Kipp <harald.kipp at egnite.de> writes:

    Harald> On 19.02.2013 17:00, Uwe Bonnes wrote:
    >> NutI2cMasterTransact() should return the number of full messages
    >> successfully transceived or return -1 in case of error. Other ideas?

    Harald> One problem with this: Sometimes the master doesn't know the
    Harald> size. In this case the slave will respond with NAK when the
    Harald> master tries to read more.

    Harald> In this case the caller needs to know how many bytes had been
    Harald> actually delivered by the slave.

I think code like

rc= NutI2cMasterTransact(bus, NutI2C_MSG *msg, size)

if (rc != size)
{
        if (rc >=0)
            num_rec = msg[rc].msg_ridx;

would retrieve how many bytes had been actually delivered by the slave for
the failing message.

Bye
-- 
Uwe Bonnes                bon at elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt
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