at32ap7000 ATMEL Corporation, at32ap7000 Datasheet - Page 56

• Manufacturer Part Number: at32ap7000
• Description: Avr 32 32-bit Microcontroller
• Manufacturer: ATMEL Corporation

32003KS–AVR32–10/07
39. USART - The DCD Signal is active high from the USART, but should be active low
40. MCI Transmit Data Register (TDR) FIFO corruption
method requires that one of the GPIO pins are available and connected externally to the
RESET_N pin. After the GPIO pin has pulled down the reset line the GPIO will be reset and
leave the pin tristated with pullup.
The DCD signal is active high from the USART, but should be active low.
Fix/Workaround
An inverter should be added on this line on the PCB.
If the number of bytes to be transmitted by the MCI is not a multiple of 4, the Transmit Data
Register (TDR) First In First Out data buffer control logic will become corrupted when trans-
mit data is written to the TDR as 32-bit values.
Fix/Workaround
Configure the MCI Mode Register (MR) to accept 8-bit data input by writing a 1 to bit 13
(FBYTE), and transfer each byte of the transmit data to TDR by right aligning the useful
value. This allows the number of bytes transferred into the TDR to match the number set up
in the BCNT field of the MCI Block Register (BLKR).
AT32AP7000
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