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+this micro-controller firmware controls a vacuum fluorescent display (VFD).
+
+the VFD has been salvaged from a Samsung SER6500 cash register.
+it already included supertex HV518 VFD drivers.
+
+the micro-controller used is a STM32F103C8T6. with the libopencm3 library.
+
+the firmware starts by testing all segments of the VFD, plays an animation, and finally displayed the text typed in over the USB CDC ACM or USART1 ports.
+
+the data is shifted out from the micro-controller to the drivers using SPI.
+a timer will periodically refresh all parts of the VFD.
+
+more details are available at https://wiki.cuvoodoo.info/doku.php?id=vfd_driver.