/technologies/fpga-group/b/blog/posts/the-art-of-fpga-design---post-28The DSP48 Primitive - Inferring larger multipliers The DSP48E2 primitive contains a signed 27x18 multiplier, any signed multiplier up to this size can be implemented with just one such primitive. If we need larger multipliers we can achieve that...en-USTelligent Community 12https://community.element14.com/technologies/fpga-group/b/blog/posts/the-art-of-fpga-design---post-28Mon, 02 Aug 2021 10:04:57 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:1d155bc5-7b82-4dce-9182-37a8ad420a35Jan Cumps1<p><span>[mention:6df0c41b821640f88ccc622506c3eacd:e9ed411860ed4f2ba0265705b8793d05]</span> I&#39;m trying to replicate the exercise. Vivado is complaining about 2 lines of code.</p><p>I&#39;ve used the <em>types_pkg</em> from <a class="jive-link-blog-small" href="/technologies/fpga-group/b/blog/posts/the-art-of-fpga-design---post-8">The Art of FPGA Design - Post 8</a> . With the functions of blog 6 added. I put all in a <a class="jive-link-external-small" href="https://gist.github.com/jancumps/622591b9a9a74c24e081a8b7407d7a1a" rel="nofollow ugc noopener" target="_blank">GIST</a>.</p><p>I&#39;m using Vivado 2020.2, that supports the VHDL2008 syntax by default.</p><p>&nbsp;</p><p>The two errors I get:</p><p>&nbsp;</p><p>[embed:dc8ab71f-3b98-42d9-b0f6-e21e02a0f8e2:3ef06e6b-9b7d-4651-b12d-db8be7f5e991:type=text&amp;text=++signal+PL%3ASFIXED_VECTOR%282+to+LATENCY%29%28P%27range%29%3A%3D%28others%3D%3ETO_SFIXED%280.0%2CP%29%29%3B]</p><div></div><p><em>Illegal subtype for subtype indication</em></p><p><em>Cannot read from &#39;out&#39; object &#39;p&#39;, use &#39;buffer&#39; or &#39;inout&#39;</em></p><p><em>&#39;p&#39; with mode &#39;out&#39; cannot be read</em></p><p>&nbsp;</p><p>&nbsp;</p><p>[embed:dc8ab71f-3b98-42d9-b0f6-e21e02a0f8e2:3ef06e6b-9b7d-4651-b12d-db8be7f5e991:type=text&amp;text=++++++PL%282%29%3C%3DRESIZE%28RA*RB%2CP%29%3B]</p><div></div><p><em>found &#39;0&#39; definitions for operator &quot;*&quot;. cannot determine exact overloaded matching definition for &quot;*&quot;</em></p><p><em>Cannot read from &#39;out&#39; object &#39;p&#39;, use &#39;buffer&#39; or &#39;inout&#39;</em></p><p><em><em>&#39;p&#39; with mode &#39;out&#39; cannot be read</em></em></p><p>&nbsp;</p><p>I am not following your blogs in order, so I may have missed something between post 6 and this one.</p><p>I&#39;m checking if there&#39;s anything related to these errors ...</p><p>&nbsp;</p><p>If you have a pointer, that would be great.</p><img src="https://community.element14.com/aggbug?PostID=7162&AppID=19&AppType=Weblog&ContentType=0" width="1" height="1">