NE866B1_Hardware_Design_Guide
1VV0301354 Rev. 6
Page
39
of
70
2018-02-28
NOTE:
According to V.24, some signal names are referred to the application
side, therefore on the NB866B1 side these signal are on the opposite
direction:
TXD on the application side will be connected to the receive line
(here named TXD)
RXD on the application side will be connected to the transmit line
(here named RXD)
For a minimum implementation, only the TXD, RXD lines can be
connected.
In order to avoid a back powering effect it is recommended to avoid
having any HIGH logic level signal applied to the digital pins of the
NB866B1 when the module is powered off or during a reboot
transition.
Using bidirectional level translators which do not support High Z
mode during power off is not recommended.
NOTE:
By default, since UART port uses the low power mode, HW flow
control is not used