As 20-or-more-year-old aircraft are overhauled, no matter how traditional the owner might be, a certain degree automation is usually introduced into the cockpit. This is done in the interest of accuracy and also to enable some analytics for the ground crew. The modern day EDM for example, relieve the human operator of the tedium of continuous control and frees the pilot to indulge in higher cognitive functions. The older the aircraft engine, the greater the need for the ground crew to analyse the aircraft performance.
The aircraft engine performance can be analysed in detail provided there is some way for the engine data to be stored and later retrieved. This is usually accomplished via onboard memory which is connected to communication ports. The latest aircraft engine data managers are usually equipped with USB ports thereby making it even easier to download engine data.
Before the onboard memory is full, the data should be downloaded and at least stored on an external hard-drive (via a PC or Laptop). At some point in time, the ground crew and connect the external hard-drive to their computer and analyse the data.
Assuming the cockpit has some degree of digital automation, transferring data accumulated onboard to a PC usually means connecting the display unit/ engine data manager via an interface cable to a PC computer. Earlier display units / engine data managers had serial ports.
One of advantages of using onboard digital indicators and data managers is the possibility of implementation of PC interface cable and providing a data link between the aircraft and ground facilities. The PC interface cable usually has a 9-pin serial connection male plug (may require external power supply). Laptops that do not have a serial port will require a Serial-to-USB Adapter so that the serial cable can be plugged into the adopter and the adopter in turn, can be plugged into the USB port of the laptop.
The hardware i.e. the PC interface cable is one part of the interface. The other part consists of the software that implements the hand-shaking protocol so the PC at one end, can “talk” to the Aircraft Fuel Flow Indicator / EDM at the other end.
The software you use will be the one that was bundled with the hardware in the cockpit. If you did not receive the software in form of a CD in the product box, you probably need to download the software separately via the manufacturer / retailer website.
For example, J.P Instruments provides the EzTrends Plotting Software that is available as a download here: https://www.jpinstruments.com/technical-support/ez-trends-download/
This patented software will transfer compressed data from your EDM to your PC via the interface cable and decompress the data. Additionally, it will also plot the data on the PC screen and provide necessary user interface to print graphs and provides flexibility in how data is displayed.
For purchase and more information on PC interface cable, please visit:- https://www.jpinstruments.com/shop/pc-interface-cable-for-edm-700-edm-800-and-edm-760/