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Altera_Forum
Honored Contributor I
1,616 Views

a problem about the memory size of onchip memory

How to design the memorysize of the onchip memory? 

when i was compilating my design , i saw a message  

"Error: Selected device has 105 RAM location(s) of type M4K. However, the current design needs more than 105 to successfully fit" 

 

My chip is EP2C35F672C6 Cyclon II family
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5 Replies
Altera_Forum
Honored Contributor I
130 Views

The Cyclone II EP2C35 has 105 M4K OnChip memory blocks. Each M4K has 4096 bits + 512 parity bits. Speaking of bytes, each M4K block has 512bytes (no parity), so if you use more than the available memory blocks, your design requires more than 105 x 512 bytes. 

 

so you have 3 options. 

1. use a bigger fpga if possible  

2. reduce the memory usage 

3. check the quartus settings, maybe some memory blocks can be swaped to registers.
Altera_Forum
Honored Contributor I
130 Views

thank you for your suggest.  

 

I have already solve the problem. 

I build the Frash memory to solve it. 

 

thank you again. 

 

 

--- Quote Start ---  

The Cyclone II EP2C35 has 105 M4K OnChip memory blocks. Each M4K has 4096 bits + 512 parity bits. Speaking of bytes, each M4K block has 512bytes (no parity), so if you use more than the available memory blocks, your design requires more than 105 x 512 bytes. 

 

so you have 3 options. 

1. use a bigger fpga if possible  

2. reduce the memory usage 

3. check the quartus settings, maybe some memory blocks can be swaped to registers. 

--- Quote End ---  

Altera_Forum
Honored Contributor I
130 Views

 

--- Quote Start ---  

thank you for your suggest.  

 

I have already solve the problem. 

I build the Frash memory to solve it. 

 

thank you again. 

--- Quote End ---  

 

 

Hi, can teach me how to build the Frash memory, i'm also getting the same error message when building a 65536x19 lpm_rom. Thanks.
Altera_Forum
Honored Contributor I
130 Views

 

--- Quote Start ---  

Hi, can teach me how to build the Frash memory, i'm also getting the same error message when building a 65536x19 lpm_rom. Thanks. 

--- Quote End ---  

 

 

Sorry, My Flash Memory doesn't successful, so I used the sdram in my project 

So, I think I can't teach you How to add the flash 

Sorry...
Altera_Forum
Honored Contributor I
130 Views

I looked at the settings but i didn't found how to swap block memory to register. Can you please tell how me i do that.

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