What are value in 8-bit high registers of TDR if 8-bit low registers are written?

[JuIn_1625121]

Hi,

At first, 16-bit data is transfered from 16-bit transmit data buffer on the RAM to TDR by using DMAC. Transfer width is 16-bit.

Next, 8-bit data is transfered from 8-bit transmit data buffer on the RAM to TDR by uing DMAC. Transfer width is 8-bit.

In this case, what values are in 8-bit high register(especially, D8)?

The customer assumes three answers.

a)0
b)Indefinite value
c)datas written at first.

d)others

Best Regards,

Inoue

[AchimE_41 · Accepted solution]

Hi,

Please see the other thread, register access is only allowed as 16 or 32bit valueFor UART, can DMACB Transfer width be used both 16bit and 8bit ?

So both will be written at the same time.

regards,

Achim