Memotech Multi-Function Expansion System

MFX

MFX Boot Screen - VGA

MFX Boot Screen - VDP

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Orders

MFX is a pretty niche "product" and is only likely to be available in very small quantities, as a result, there isn't a formal method for ordering one. If you would be interested in purchasing one, please drop me an email via the link on the bottom of this page.

 Depending on the availability of the component parts, particularly the FPGA module, I should be able to give you an indication of the current availability and lead time for MFX. Orders will be fulfilled on a first come, first served basis.

On the subject of the FPGA module, availability is not the only issue that I am having. Whilst supplies are becoming more readily available from quite a few of the Chinese resellers, the quality of the boards is very variable, to such an extent that, when I can obtain them, I am seeing failure rates of 25-40%, e.g., from one supplier 1 board in 4 was faulty, from another, 2 from 5.

When faults occur, the core FPGA itself tends to appear to be working and the device can be programmed/verified, but one or more of the I/O ports proves to be faulty. I'd hazard a guess that, even if the fabricator does some testing of the board, they are only checking the device responds and not exercising the I/O. It is also possible that many of these boards are being assembled using factory reject FPGAs.

This has led to a number of symptoms when installed in an MFX, including the complete lack of VGA output, single VGA colour bit(s) missing and failure to detect the SD card. There have been a couple of instances where it has been obvious that poor quality soldering of the TQFP package has been to blame, on other boards, the soldering can appear to be fine and the FPGA apparently has an internal fault with one or more I/O pins.

These details are likely not of interest to many people, but as noted here to give a little background on why the MFX price has turned out to be a little higher than intended.

M F X   U S E R B A S E

* EP2C5 Altera Cyclone II EP2C5T144C8N  Logic Elements 4608, RAM 119,808 bits, I/O Pins 81 of 81 used

EP4CE6 Altera Cyclone IV EP4CE6E22C8N Logic Elements 6000, RAM 276,480 bits, I/O Pins 81 of 87 used