MIBSPI BITERRFLG and SIMOFUN[1]

Hideaki Nambu

Mastermind 9125 points

Sirs,

Is it possible to set BITERRFLG=1 when all the following condition meet?:

SIMOFUN[1]=1, that is, MIBSPI1SIMO[1] used.
But the PINMMR14[1]=0, that is, MIBSPI1SIMO[1] not used.
Pin#106 have 3.3 volts.
MIBSPI1 starts in 4-wire mode as master.

The part# is TMS57021xxCPGEQQ1.

My customer reported MIBSPI1.SPIFLG.BITERRFLG=1.

The BITERRFLG bit description in the TRM didn't explain our case. SIMO transitions fast and is stable at the half clock later.

But when we disconnected 3.3 volt pin #106, the phenomenon stopped.

Therefore we are intersted in the PINMMR14[1] and MIBSPI1SIMO[1].

over 9 years ago

0 Enrique Lizarraga over 9 years ago

TI__Expert 4580 points

Hello:

From the SPI peripheral point of view, that pin is still functionally assigned to it, even if your are assigning it to a different function in PINMUX. The right way would be to set that pin mode to GIO (SIMOFUN[1]=0).

Regards,

Enrique

0 Hideaki Nambu over 9 years ago in reply to Enrique Lizarraga

Mastermind 9125 points

Hello Enrique,

Then what is controlled by the bit PINMMR14[1] ?

Does the bit connects/disconnects MIBSPI1SIMO[1] to pin#106, but the point is OUTPUT ONLY ?

-n

0 Vineeth Thomas Alex over 9 years ago in reply to Hideaki Nambu

TI__Intellectual 1855 points

Hi,

Your understanding is correct. The PINMMR[] only determines what peripheral function(internal) is tied to the board pin(external). In your case, the PINMMR14[] controls which function is tied to the output of pin#106 :- whether it is N2HET1[18] or MIBSPI1SIMO[1]. For the case of input (without input muxing), all functions connected to a pin will receive the input signal given to the pin.

You can find more info on this in the TRM( I/O Multiplexing and Control Module (IOMM) > Control of Multiplexed Functions > Control of Multiplexed Outputs )

Thanks and Regards,

Vineeth

0 Hideaki Nambu over 9 years ago in reply to Vineeth Thomas Alex

Mastermind 9125 points

Vineeth and Enrique,
As you pointed out the TRM p.225 tells about my quesions and more details. Thank you very much.
-n

Arm-based microcontrollers

Arm-based microcontrollers forum

MIBSPI BITERRFLG and SIMOFUN[1]