Nowadays, FPGA Mezzanine Card has become a topic of great interest and relevance in today's society. With the constant advancement of technology and globalization, FPGA Mezzanine Card has acquired a fundamental role in our daily lives. From its impact on the economy and politics, to its influence on culture and entertainment, FPGA Mezzanine Card has managed to capture the attention of people of all ages and backgrounds. In this article we will explore in depth the various aspects related to FPGA Mezzanine Card, analyzing its importance, its implications and its evolution over time. What is the true impact of FPGA Mezzanine Card on our society? How has our way of seeing and living FPGA Mezzanine Card changed over the years? These are some of the questions that we will try to answer throughout this exhaustive analysis.
This article needs to be updated. The reason given is: information on FMC+ should be added. (November 2023) |

FPGA Mezzanine Card (FMC) is an ANSI/VITA (VMEbus International Trade Association) 57.1 standard that defines I/O mezzanine modules with connection to an FPGA or other device with re-configurable I/O capability.[1][2] It specifies a low profile connector and compact board size for compatibility with several industry standard slot card, blade, low profile motherboard, and mezzanine form factors.
The FMC specification defines:[3]
The FMC specification has two defined sizes: single width (69 mm) and double width (139 mm). The depth of both is about 76.5 mm.[4] The FMC mezzanine module uses a high-pin count 400 pin high-speed array connector. A mechanically compatible low pin count connector with 160 pins can also be used with any of the form factors in the standard.
FMC allows for two sizes of connector, Low Pin Count (LPC) and High Pin Count (HPC), each offering different (maximum) levels of connectivity,[5] analogous to how some PMC boards have a 32-bit interface while others have a 64-bit interface by using an additional connector. "The LPC connector provides 68 user-defined, single-ended signals or 34 user-defined, differential pairs. The HPC connector provides 160 user-defined, single-ended signals (or 80 user-defined, differential pairs), 10 serial transceiver pairs, and additional clocks. The HPC and LPC connectors use the same mechanical connector. The only difference is which signals are actually populated. Thus, cards with LPC connectors can be plugged into HPC sites, and if properly designed, HPC cards can offer a subset of functionality when plugged into an LPC site."[6]
FMC provides a Geographical Address using two pins (GA1:GA0) that are typically used by a mezzanine device to determine which FMC connector on a carrier it is attached to. For cards that have only one FMC connector, the default geographical address is 00.
Some FMC mezzanine cards may attach other devices to the I2C bus and address them through a system controller, using the geographical address as a chip-select. This is not strictly in adherence with the FMC specification.