ThingMagic Mercury6e M6e-30dBm, Hardware Manual

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Hardware Interfaces
18
Hardware Overview
TTL Level TX
V-Low: Max 0.4 VDC
V-High: 2.1 to 3.3 VDC
8 mA max
TTL Level RX
V-Low: -0.3 to 0.6 VDC
V-High: 2.2 to 5 VDC
(Tied to ground through a 10kOhm pull-up resistor. It is not harmful, but not
recommended to drive the input above 3.3 V.)
A level converter could be necessary to interface to other devices that use standard 12V
RS232. Only three pins are required for serial communication (TX, RX, and GND).
Hardware handshaking is not supported. The M6e serial port has an interrupt-driven
FIFO that empties into a circular buffer.
The connected host processor’s receiver must have the capability to receive up to 256
bytes of data at a time without overflowing.
Baud rates supported:
– 9600
– 19200
– 38400
– 115200
– 230400
– 460800
– 921600
Note
The baudrate in the
Boot Loader
mode depends on whether the module
entered the bootloader mode after a power-up or through an assert or “boot
bootloader” user command. Upon power up if the
Reset Line
is LOW then the
default baud rate of 9600 will be used. If the module returns to the
bootloader from
Application Firmware
mode, then the current state and
baudrate will be retained.
USB Interface
Supports USB 2.0 full speed device port (12 Megabits per second) using the two USB
pins (USB_DM and USB_DP).