Uart 7816 Control Register (Uartx_C7816) - NXP Semiconductors MKL27Z128VFM4 Reference Manual

Memory map and registers
Field
0 If C2[RIE] and S1[RDRF] are set, the RDFR interrupt request signal is asserted to request an interrupt
service.
1 If C2[RIE] and S1[RDRF] are set, the RDRF DMA request signal is asserted to request a DMA
transfer.
4 This field is reserved.
Reserved This read-only field is reserved and always has the value 0.
Reserved This field is reserved.
This read-only field is reserved and always has the value 0.

38.4.13 UART 7816 Control Register (UARTx_C7816)

The C7816 register is the primary control register for ISO-7816 specific functionality.
This register is specific to 7816 functionality and the values in this register have no effect
on UART operation and should be ignored if ISO_7816E is not set/enabled. This register
may be read at any time but values must be changed only when ISO_7816E is not set.
Address: 4006_C000h base + 18h offset = 4006_C018h
Bit 7
Read
Write
Reset
0
Field
7–5 This field is reserved.
Reserved This read-only field is reserved and always has the value 0.
4 Generate NACK on Overflow
ONACK
When this field is set, the receiver automatically generates a NACK response if a receive buffer overrun
occurs, as indicated by S1[OR]. In many systems, this results in the transmitter resending the packet that
overflowed until the retransmit threshold for that transmitter is reached. A NACK is generated only if
TTYPE=0. This field operates independently of ANACK. See .
0 The received data does not generate a NACK when the receipt of the data results in an overflow
event.
1 If the receiver buffer overflows, a NACK is automatically sent on a received character.
3 Generate NACK on Error
ANACK
When this field is set, the receiver automatically generates a NACK response if a parity error occurs or if
INIT is set and an invalid initial character is detected. A NACK is generated only if TTYPE = 0. If ANACK is
set, the UART attempts to retransmit the data indefinitely. To stop retransmission attempts, clear C2[TE]
or ISO_7816E and do not set until S1[TC] sets C2[TE] again.
696
UARTx_C5 field descriptions (continued)
6 5
0
ONACK
0 0
UARTx_C7816 field descriptions
Table continues on the next page...
KL27 Sub-Family Reference Manual , Rev. 5, 01/2016
Description
4 3
ANACK INIT
0 0
Description
Overrun NACK considerations
2 1
TTYPE ISO_7816E
0 0
Freescale Semiconductor, Inc.
0
0