How to build a two processor system?

<div class='quotetop'>QUOTE (babysnow @ Jul 28 2009, 03:59 AM) <{post_snapback}> (index.php?act=findpost&pid=23293)</div>

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How many Jtag-Uarts are needed, if I use two cpus?[/b]

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None. You don&#39;t need a JTAG uart to get uClinux running on a CPU. I suppose you also can use one or two. The "NIOS2 -terminal" program supports an "instance" paramter that I think is used to distinguish between several JTAG UARTS on the same JTAG interface.

<div class='quotetop'>QUOTE (babysnow @ Jul 28 2009, 03:59 AM) <{post_snapback}> (index.php?act=findpost&pid=23293)</div>

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The purpose of my multiprocessor project is to do paralell working.A uclinux system with several piece of working programs.

One storage space can only be accessed by one periphery at a time.How could make the parelell (several programs) work together?[/b]

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I don&#39;t suppose it makes much sense to have two CPUs run two separate Linux OSes on the same Avalon bus, as the bus arbitration and queuing memory accesses will slow down both a lot. A more sophisticated design with one Linux system and a simple system as coprocessor usually is much more viable.

-Michael

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None. You don&#39;t need a JTAG uart to get uClinux running on a CPU. I suppose you also can use one or two. The "NIOS2 -terminal" program supports an "instance" paramter that I think is used to distinguish between several JTAG UARTS on the same JTAG interface.[/b]

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But, in the SOPCBuilder, if a JTAG-UART module is added, then it can only be connected to ONE cpu.

And I have made a test that if use only one jtag module in the SOPCBuilder, then the cpu without connection with jtag cannot worked.

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I don&#39;t suppose it makes much sense to have two CPUs run two separate Linux OSes on the same Avalon bus, as the bus arbitration and queuing memory accesses will slow down both a lot. A more sophisticated design with one Linux system and a simple system as coprocessor usually is much more viable.[/b]

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I mean several programs without system, and a uclinux system. Is there any method to make the programs running paralelly?

<div class='quotetop'>QUOTE (babysnow @ Jul 28 2009, 01:56 PM) <{post_snapback}> (index.php?act=findpost&pid=23300)</div>

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in the SOPCBuilder, if a JTAG-UART module is added, then it can only be connected to ONE cpu.[/b]

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I&#39;m not an expert with Quartus, Maybe somebody else can help.

<div class='quotetop'>QUOTE (babysnow @ Jul 28 2009, 01:56 PM) <{post_snapback}> (index.php?act=findpost&pid=23300)</div>

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And I have made a test that if use only one jtag module in the SOPCBuilder, then the cpu without connection with jtag cannot worked.[/b]

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You can configure a Fifoed UART module (free IP core) and connect RxD and TxD to some pins. Now (if using Linux on that CPU) you can configure the serial UART in the uClinux configuration (see the Wiki how to do that) and connect those pins to some kind of Terminal (PC).

<div class='quotetop'>QUOTE (babysnow @ Jul 28 2009, 01:56 PM) <{post_snapback}> (index.php?act=findpost&pid=23300)</div>

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I mean several programs without system, and a uclinux system. Is there any method to make the programs running paralelly?[/b]

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If you have enough resources in the FPGA you can do multiple CPUs. I don&#39;t see what should prevent them from running in parallel.

-Michael

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If you have enough resources in the FPGA you can do multiple CPUs. I don&#39;t see what should prevent them from running in parallel.[/b]

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If I put the program all in sdram storage space , sdram can be accessed only by one peripherial at a time.

<div class='quotetop'>QUOTE (babysnow @ Jul 28 2009, 03:54 PM) <{post_snapback}> (index.php?act=findpost&pid=23305)</div>

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If I put the program all in sdram storage space , sdram can be accessed only by one peripherial at a time.[/b]

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That is a bad idea, as - you said it - the RAM accesses need to be queued and thus the CPUs are slowed down.

You should use tightly couples memory for all your coprocessor CPUs as well for program as for data.

-Michael