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  3. Following Bus connections

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Following Bus connections

PatrikOsgnach
PatrikOsgnach over 9 years ago

Hello,

I am writing a skill script that allows the user to follow a net through the instances it is connected to and I am facing a problem regarding how to deal with buses.

Let's consider this schematic:

I have clicked on the net A<3:0>, which is a 4 bit bus, and I want to know how it is connected

(car (geGetSelSet))~>net~>?? tells me that it is connected to instances I5 and C0<3:0> only (I looked at allInstTerms and instTerms properties) but the signal field allows me to know how individual signals are connected

(caddr (car (geGetSelSet))~>net~>signals)~>name is A<1>

(mapcar 'car (caddr (car (geGetSelSet))~>net~>signals)~>memInstTerms)~>inst~>name tells me that A<3> is connected to these instances: C0<3:0> I5 I7

(mapcar 'car (caddr (car (geGetSelSet))~>net~>signals)~>memInstTerms)~>name tells me ("PLUS" "P1<3:0>" "P2<1:0>") so A<1> is connected to P1<3:0> on instance I5 and P2<1:0> on instance I7

now, I want to know on which input bit is A<1> connected to.

(mapcar 'cadr (caddr (car (geGetSelSet))~>net~>signals)~>memInstTerms) tells me (2 2 0) so I expect that A<1> connects to bit 2 (counting from 0) of P1<3:0>, which is P1<1> and to bit 0 of P2<1:0> which is P2<1>.

Is this reasoning correct? I need to know this because I need to follow A<1> on its path inside instances I5 and I7. Same for all other bits

Thank you and best regards,

Patrik

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