Dear Support, I installed alliance-3.2b on freebsd a few days ago with the aim to investigate its suitability for VHDL (behavioural) - Silicon_foundry_synthesis. Even VHDL (behavioural) - VHDL (structural) would be a good first step for me. At present, I am still learning and reading up on the various tools available. I started off with the addaccu tutorial, but with the following difference: 1) 'addaccu.vbe' compiles and simulates with asimut (to be expected). 2) I then use bop to generate 'addaccu-bop.vbe' from 'addaccu.vbe'. It compiles and simulates with asimut. 3) I then use scmap to generate 'addaccu-scmap.vst' from 'addaccu-bop.vbe'. It compiles with asimut (no errors). It gives the following errors when I want to simulate it: Error 111: illegal connection on signal 's 1' Error 111: illegal connection on signal 's 2' Warning 3: signal 'vdde' never used. Warning 3: signal 'vsse' never used. cannot continue further more. Have a nice day... The circuit 'addaccu-scmap.vst' is to big to completely trace, but I can see that the signals s(1) and s(2) are used both as outputs and fed back into the circuit again. (In modern VHDL such signals will be declared as 'buffer'.) Now my question: Am I doing something wrong or is there a problem with scmap and asimut? (scmap gives a wrong circuit and asimut compiles it without warning.) I would be grateful for any advice in this regard, but keep in mind, I am still new with alliance. Best wishes, Bertie Kemp PICO Systems cc.