11 Feb
2007
11 Feb
'07
6:38 p.m.
On 2/11/07, Grant Stockly <grant at stockly.com> wrote:
How does that add up to 1024 instead of 2048? A single block as shown
on the page in the above link has 256 fuses doesn't it? And there are
8 of those blocks? So 256 * 8 = 2048 fuses?
Looks like the 16R8 has 8 inputs, 8 D/Q outputs
with feedback, 1 clock
input, and 1 output enable input. Looks like there are 32 columns (8x
input True/False plus 8x D/Q feedback True/False) and 64 rows (8x
product terms into each D/Q output) for a total of 2048 fuses. So I
think that would be 256x8, not 512x8.
1024 fuses is right. Talking about "looks", I just happen to have pictures
of the silicon on a MMI 16R8 HAL. A HAL is just a manufactured PAL.
http://www.stockly.com/forums/showthread.php?t=18