A method of converting serial data to parallel data by an electronic measuring device which includes a detection channel module, a sampling module, a control unit, a data path selector and a memory device, comprising the steps of:
- a. connecting an external signal terminal to receive serial data by the detection channel module;
- b. enabling a predetermined number of a plurality detection channels of the detection channel module to be used for signal sampling by the control unit;
- c. converting the serial data into parallel data bytes by a plurality of serial-to-parallel converters of the sampling module, wherein the detection channel module receives the serial data and the sampling module converts the serial data into the parallel data bytes;
- and
- d. storing the parallel data bytes into the memory device, where the sampling module includes a plurality of first-in-first-out (FIFO) registers, the parallel data bytes are deposited into the FIFO registers, and the data path selector outputs the parallel data bytes from the FIFO registers into the memory device for storage;
- the FIFO registers are respectively connected to the serial-to-parallel converters which are respectively connected to the detection channels;
- the memory device includes a memory controller and a storage unit, and the memory controller causes the parallel data bytes to be input into the storage unit in sequential order;
- the storage unit includes a plurality of storage sectors, a first indicator and a second indicator, wherein each storage sector has the same number of bits as each of the parallel data bytes transferred from the data path selector, the first indicator is pointed to the storage sector where a first parallel data byte from the data path selector is predetermined to be stored in, and the second indicator is pointed to another storage sector where the memory controller causes a next parallel data byte to be stored in,
- wherein all the parallel data bytes stored in the FIFO registers are transferred and stored in the storage unit in sequential order;
- as the parallel data bytes continue to be input into the storage unit, the second indicator continues to point to the next storage sector until the storage unit reaches the full capacity;
- when the storage unit reaches full capacity, the second indicator is pointed to the same storage sector at which the first indicator is pointed to, and the first indicator is then moved to be pointed to another storage sector based on the predetermined number of the enabled detection channels.