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Altera_Forum's avatar
Altera_Forum
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8 years ago

Data is read before accumulation is finished

=============================================================== for(uint t = 0; t < loop_cnt; t++) { //load data to data buffer for(uint w = 0; w < TILE_WIDTH; w++) { ...
Altera_Forum's avatar
Altera_Forum
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8 years ago

Hi HRZ,

Thanks for your advice, I removed the initialization part and declared a variable in the accumulation loop called last_sum, which is 0 when t is 0 and the current accumulator value when t is greater than 0, and it resolves the problem. I have 2 more questions:

1. With TILE_WIDTH = 4 and TILE_HEIGHT = 4, The "output" buffer is supposed be be duplicated 16 times (I intentionally made it BRAM), but in the report it takes 32 BRAMS. Where does this 2 times more replication come from?

2. In the report, there's 16 simultaneous thread launched for the loop controlled by t, does this mean pipelining? If yes, this loop is not pipelinable, due to the data dependency on "output" buffer.

Any advice would be greatly appreciated!