Request to revise I2S section of HAL document. (UM1725)

[KAJIK.1]

Hello,

In Section 36. I2S Generic Driver of HAL document (UM1725), I found an incorrect or misleading explanation.

In the explanation of HAL_I2S_Transmit, there is a "notes" below.

-----------------

HAL_I2S_Transmit (I2S_HandleTypeDef * hi2s, uint16_t * pData, uint16_t Size, uint32_t Timeout)

Notes: When a 16-bit data frame or a 16-bit data frame extended is selected during the I2S configuration phase, the Size parameter means the number of 16-bit data length in the transaction

and when a 24-bit data frame or a 32-bit data

frame is selected the Size parameter means the number of 16-bit data length.

-----------------

(Same explanation is shown many times in the source code of stm32f4xx_hal_i2s.c.)

However, Code is implemented as below.

 if ((tmpreg_cfgr == I2S_DATAFORMAT_24B) || (tmpreg_cfgr == I2S_DATAFORMAT_32B))
 {
 hi2s->TxXferSize = (Size << 1U);
 hi2s->TxXferCount = (Size << 1U);
 }
 else
 {
 hi2s->TxXferSize = Size;
 hi2s->TxXferCount = Size;
 }

That means,

when a 24-bit data frame or a 32-bit data

frame is selected the Size parameter means the number of 16-bit 24/32-bit data length. (or the number of 24/32-bit data)

Original explanation is incorrect or misleading for the beginner like me, please consider to change as above.

Thanks,

[Imen GH]

Hello,

I have raised your feedback internally to take into consideration.

Imen

[KAJIK.1]

Dear Imen,

Many Thanks for your kind reply.

And please convey my appreciation for the great effort of HAL team.

K.A.

[Imen GH]

​Hello @KAJIK.1​,

Thanks  

You are welcome.

[LFerr.1]

Hi all,

I've a different question on the same topic: what does "length in transaction" mean?

Thanks

L.F.

[waclawek.jan]

"number of 16-bit data length in the transaction" supposedly means "number of data, 16-bit long, in the transaction".

I am not native English speaker either...

JW