void vfd_off(void)
switch VFD display off
void vfd_digit(uint8_t nb, char c)
set character to digit block
void vfd_setup(void)
setup VFD
void vfd_clear(void)
clear VFD display
void vfd_matrix(uint8_t nb, char c)
set character to matrix block
void vfd_on(void)
switch VFD on
void vfd_test(void)
test VFD display (light up all segments)