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Altera_Forum
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10 years ago

Why does an output only 8-bit wide PIO use/needs 16 memory locations (0x2010-0x201F)?

Hi all, I'm new to the Nios/Qsys/Eclipse. I've used Quartus software before but never with Nios. I'm using a Nios Gen2 with a MAX10 (BeMicroMAX10). The free version of Nios. The bas...
Altera_Forum's avatar
Altera_Forum
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10 years ago

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You should also make your slave 32bits wide - return 0 to reads for the top 24 bits.

The Nios acceses are 32bit (with appropriate byte enables for writes) and logic gets added to generate 4 cycles to an 8bit slave.

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Do You suggest to make all PIO registers ( connected to NIOS II as slaves in QSys ) 32-bits wide even though only several bits are used?

What C type variable should then be used?

Apparently, unsigned int ?