topic Re: iMX6Solo : Register setting for using the RXC,RXFS signals instead of the TXC,TXFS signals in i.MX Processors

iMX6Solo : Register setting for using the RXC,RXFS signals instead of the TXC,TXFS signals

koichisakagami — Mon, 13 Apr 2015 09:19:48 GMT

Dear community,

We designed the custom board wrongly as follows.

The i.MX6Solo (slave) is connected to the DSP(master) with RXC,RXFS,RXD,TXD signals
in synchronous mode (4-Wire interface).

In reference manual 16.5.1.3.1 Synchronous Mode (4-Wire Interface),
it is described that a 4-wire interface use TXC, TXFS,RXD,TXD signals.

[Background]
We referred the Reference manual sect.16.6.7 "Port Timing Control Register 4 (AUDMUX_PTCR4)" .

We set the AUDMUX_PTCR4 register to h'4210_8800 ".
AUDMUX_PTCR4 :
TCSEL[3:0] - 1xxx Selects RXC from port.
TFSEL[3:0] - 1xxx Selects RXFS from port.

As a result, the i.MX6 4-wire interface does not work correctly.

In order to verify the register settings without "Port Timing Control Register 4 (AUDMUX_PTCR4)" ,
we modified the hardware connection between i.MX6 and DSP with RXC , RXFS signals.
Now the i.MX6Solo (slave) is connected to the DSP(master) with TXC, TXFS,RXD,TXD signals
in synchronous mode (4-Wire interface).
Then i.MX6Solo 4-wire interface work correctly.
We think that the register settings without AUDMUX_PTCR4 are approximately correct.

[Question]
Is the AUDMUX_PTCR4 vaule wrong ?
Is it necessary to set the other registers other than AUDMUX_PTCR4 register ?
Could you advise to us any hints ?

Best Regards,
Koichi Sakagami

Re: iMX6Solo : Register setting for using the RXC,RXFS signals instead of the TXC,TXFS signals

igorpadykov — Mon, 13 Apr 2015 11:37:09 GMT

Hi koichi

if you selected in PTCR4 RXC, RXFS as inputs,

then RFSEL,RCSEL settings are ignored in PTCR4 -

TFSEL,TCSEL should be selected in appropriate PTCR1,2

and selection as you set:

	TCSEL[3:0] - 1xxx Selects RXC from port.
	TFSEL[3:0] - 1xxx Selects RXFS from port.

Best regards

igor

Re: iMX6Solo : Register setting for using the RXC,RXFS signals instead of the TXC,TXFS signals

koichisakagami — Thu, 16 Apr 2015 09:50:44 GMT

Dear Igor san,

Thank you for reply.

We read AUDMUX description and this comunity thread, and tried.

But failed.

Current setting is:

SSI1 -> internal port 1 -> Ext port 4

So I modified PTCR1 from 0x9CC00800 to 0xDEC00800

TFS_DIR: 1
TFSEL[3:0] : Changed from b'0011(TXFS, Port4) to b'1011(RxFS, Port4)

TCLKDIR: 1
TCSEL[3:0]: Changed from b'0011(TXC, Port4) to b'1011(RxC, Port4)

And tried, but still can not transfer any data out.

Please ask if there is any other modification needed.

Best Regards,
Koichi Sakagami

Re: iMX6Solo : Register setting for using the RXC,RXFS signals instead of the TXC,TXFS signals

igorpadykov — Thu, 16 Apr 2015 12:47:42 GMT

Hi koichi

I think settings are correct,

however I do not have idea why it is not

working. I would suggest to test with SDK i.MX 6Series Platform SDK :

Bare-metal SDK, to avoid linux side effects.

Best regards

igor