The LCD_E peripheral module on the
MSP430FR4131 MCU can support up to 8-MUX displays with 256 segments or 4-MUX with 144
segment displays, as used in this design with the FH-1152P LCD. In the PCB layout-driven
design process, LCD_E offers fully-software-configurable segment S and common COM
signals which are connected to the respective MSP430 device pins. This enables an
optimized routing of the PCB which avoids signal crossings and keeps signals on one side
of the PCB only, here the top layer. If the internal charge pump of the LCD module is
used, place the externally provided capacitor on the LCDCAP0 and LCDCAP1 pins as close
as possible to the MCU. Connect the capacitor to the device using a short and direct
trace. TI recommends using the VLO on-chip oscillator for the lowest system cost. The
ultra-low power VLO has an accuracy of 10 kHz ±50% so calibrate the VLO against the ±1%
accurate on-chip 16-MHz digitally-controlled oscillator (DCO) with frequency-locked loop
(FLL).
Alternatively, a 32.768-kHz
clock output from MSPM0G3507 device can be provided to the MSP430FR4131 using a GPIO
output.