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CHess4's avatar
CHess4
Icon for New Contributor rankNew Contributor
7 years ago

Getting started resources for MAX 7000

Hi,

I am starting to develop with CPLDs, and​ when looking for basic MAX 7000 circuits, I don't find anything on the net. Is there a sample basic circuit for integrating a MAX 7000A into a schematic? Showing which connections have to be made for it to work? Or is there a schematics of a simple development board that I could copy from? I am using it in combinatorial mode without clock, with 3V3 inputs, and I would like to program it in-circuit using an ARM microcontroller that is part of the same circuit or external JTAG programmer connected via pin header. I am using altium 16.

I will be using the 7032 or 7064 version with PLCC 1.27MM pitch package, as I am soldering the prototypes myself. Any link to beginners resources will be greatly appreciated. Especially to circuit design for integrating those CPLDs.

Thanks and best regards,

Chris (Germany)​

​

6 Replies

    • CHess4's avatar
      CHess4
      Icon for New Contributor rankNew Contributor
      Hi, thank you, there are no schematics in that document. Where can I find sample schematics with power supply and in circuit programmability, ideally by a microcontroller?
      • ak6dn's avatar
        ak6dn
        Icon for Regular Contributor rankRegular Contributor

        If you are not using any clocked FFs then you don't need a clock source and can operate purely combinatorial logic.

        For sure you need to understand the max current drive limits for the I/Os. Datasheet will tell you the limits.

        The 7000A series is 3.3V supply and I/O voltage, but the I/Os are 5V tolerant. So you can add a pullup to +5V tied to an output if need be.

        JTAG is its own protocol (NOT the same as UART/SPI/I2C). So unless you have a JTAG knowledgeable master (like an Altera ByteBlaster) you will have to connect the JTAG pins to standard I/O ports on your micro, and then write the code that simulates the JTAG protocol. Be aware however that writing the code on a micro that does low level JTAG (ie, bit banging TCK/TMS/TDI/TDO correctly) is just a very small part of the problem. Writing all the code that implements full device programming thru JTAG is a whole other significant project. Old Altera used to supply source code for such a function (the old JAM STAPL player) but I don't know if that is still around now that Intel has assumed control.

        Personally I would recommend getting an Altera USB Blaster clone (Terasic has a nice one that is 100% Altera compatible that is inexpensive).