ThingMagic M6e - Manual (Page 27)

Hardware Interfaces
A D I V I S I O N O F T R I M B L E
Hardware Overview 27
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 115200 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).
General Purpose Input/Output (GPIO)
The four GPIO connections, provided through the M6e Digital Connector Signal Definition ,
may be configured as inputs or outputs using the MercuryAPI. The GPIO pins connect
through 100 ohm resistors to the high current PA0 to PA3 pins of the AT91SAM7X
processor. The processor data sheet can be consulted for additional details.
Pins configured as inputs must not have input voltages that exceed voltage range of -0.3
volts to +5.5 volts. In addition, during reset the input voltages should not exceed 3.3V.
Outputs may source and sink 16 mA. Voltage drop in the series 100 ohm resistor will
reduce the delivered voltage swing for output loads that draw significant current.
Input Mode
– TTL compatible inputs,
– Logic low < 0.8 V,
– Logic high > 2.0V.
– 5V tolerant
Output Mode
– 3.3 Volt CMOS Logic Output with 100 ohms in series.
– Greater than 1.9 Volts when sourcing 8 mA.
– Greater than 2.9 Volts when sourcing 0.3 mA.
– Less than 1.2 Volts when sinking 8 mA.
– Less than 0.2 Volts when sinking 0.3 mA.
Module power consumption can be adversely affected by incorrect GPIO configuration.
Similarly, the power consumption of external equipment connected to the GPIOs can also