I want to create a mini PCIe card board that is going to connect to computer and can also be used as a general propose board to connect to other external boards. When connecting to computer is going to use only USB communication so just two pins of the mini PCIe connector. The board will contain a microcontroller and a sensor with in SPI communication. The question is in which pins of the PCIe connector can I connect the pins of the microcontroller that are connected to the SPI and the sensor without disturbing the communication of the microcontroller and sensor? The reason I want to do that is to be able later to connect other chips to the SPI when the card is not connected to the computer and used as a general propose board.
From my understand,you should let the PCIe board has two functions,one is to connect to a PC as a general PCI card,another is to use the board as a main micro-controller to control other thing.I think you should read the sensor value with the on-board MCU,couldn't you ?
Actually,the easy way is to check the offical PCIe specification documents to judge which pins you can use in double reasons.
From my understand,you should let the PCIe board has two functions,one is to connect to a PC as a general PCI card,another is to use the board as a main micro-controller to control other thing.I think you should read the sensor value with the on-board MCU,couldn't you ?
Actually,the easy way is to check the offical PCIe specification documents to judge which pins you can use in double reasons.