| 摘要 |
In a gas meter with two ultrasonic transducers facing each other in the pipe, the electronic processing unit incorporates a microcontroller connected to a transmitter and receiver comprising operational amplifiers and a D-A and A-D convertor respectively, switched between the transducers alternately. Within the microcontroller, a first-in first-out shift register memory, an EEPROM and a read-only memory for instructions are associated with a sequencer, an arithmetic and logic unit and accumulator registers linked to address and data buses. |
