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Altera_Forum
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7 years ago

ALTACCUMULATE not working in Quartus 17.1

I am migrating from Quartus 13.1 on a 32 bit Windows 7 to 17.1 on 64 bit Windows 10. My 1000 lines of AHDL code involving LVDS at 960MHz with a Nios II processor and tons of altera megafunctions h...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
7 years ago

ALTACCUMULATE is working fine. Actually it was some timing issue writing to a TRI_STATE_BUS which feeds internal logic. Strangely this behavior occurs for loop lengths of greater than 10.

When I added the nop below everything became alright!

psrc = (PUSHORT)(DPR_BASE);

pdest = (PUSHORT)(AHDL_IFACE_BASE);

for (i=0; i<15; i++)

{

*pdest++ = *psrc++;

asm("nop");

}

These pointers are always more elegant than the macros:

IOWR_16DIRECT(DPR_BASE, offset, val)

IORD_16DIRECT(DPR_BASE, offset)

Regards,

Ravi