Microcontroller displays multiple chart or oscilloscope timing ticks

摘要

While working with a 10-bit DI-184 module from Dataq to monitor and display vibration-sensor data, I found that, although the chart displays a time index, this time reference is not visible in the saved file. You can add time ticks, representing seconds or minutes, to a chart graphic by using a simple and inexpensive crystal-based microcontroller to generate a sequence of tags on a dedicated chart channel. Figure 1 shows a small, eight-pin 12F508 microcontroller from Microchip Technology (www.microchip. com) that provides multiple timing ticks. Listing 1, the microcontroller's program is available in the Web version of this Design Idea at www.edn.com/ 080501di3. It offers four timing sequences. You can select a timing sequence by strapping pins 4 and 6 (Table 1, also at www.edn.com/080501di3).