Initializing data in EAB ram

[rickman]

I am using an EAB as a RAM for program storage for an MCU in an Altera
ACEX FPGA. But I can't seem to find info on how to initialize the RAM.
I will at least need a boot strap program to read an external Flash into
the RAM. I found information about creating MIF files and RIF files.
But they don't say much about how they get used. Can anyone give me the
details? I assume this initialization data goes into the bit stream
using the tools, no? Is there a way to initialize the RAM in a VHDL
simulation other than to use the variable initialization of VHDL? That
seems very messy.

If the EABs can not be initialized, I guess I will have to provide an
external means of loading the RAM after the chip has been configured.

--

Rick "rickman" Collins

rick.collins@XYarius.com
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[Rajeev]

rickman <spamgoeshere4@yahoo.com> wrote in message news:<40D7CE00.DE3256AC@yahoo.com>...

I am using an EAB as a RAM for program storage for an MCU in an Altera
ACEX FPGA. But I can't seem to find info on how to initialize the RAM.
I will at least need a boot strap program to read an external Flash into
the RAM. I found information about creating MIF files and RIF files.
But they don't say much about how they get used. Can anyone give me the
details? I assume this initialization data goes into the bit stream

My recommendation is to use the MegaWizard plugin manager and examine the
generated VHDL to see how they do it, then you have the option to roll your
own. Basically you pass the MIF file as a Generic to the instantiated
component. It works smoothly. That is, for Stratix... The options for ACEX
may be different.

COMPONENT altsyncram
GENERIC (
<...>
INIT_FILE : STRING := "YourFile.mif";
INIT_FILE_LAYOUT : STRING := "PORT_A";
);

using the tools, no? Is there a way to initialize the RAM in a VHDL
simulation other than to use the variable initialization of VHDL? That
seems very messy.

Yes. See the Quartus Help on Opening Embedded RAM, and Update Simulator
with Current Memory. You have to insert a simulation breakpoint and do
it then... (Though at this very moment I'm trying to do this with a MegaRAM,
and struggling.)

Hope this helps,
-rajeev-