While trying to edit an imported symbol (which consists of three sub-symbols in total) from an external source, I noticed that in eeschema one can use each of the sub-symbols (say A, B and C) as required but if one needs to edit the symbol in symbol editor, it offers/displays only one sub-symbol for editing. In my case the sub-symbol A only is offered for editing. The sub-symbols B and C are not shown/offered.
Then, just out of curiosity I tried the TTL device 74LS74 (Dual D-Flip-Flop) in KiCad symbol library. It consists of three sub-symbols in total and in eeschema each one of them can be selected individually. But also here, if one tries to edit it, the symbol editor shows/offers only sub-symbol A for editing. The sub-symbols B and C are not offered also in this case.
My question: why is only one sub-symbol offered for editing? Are the other sub-symbols updated automatically by KiCad or they are available somewhere else? Only that I just can’t find them.
To avoid unnecessary search on your side I must add that in both cases cited above the sub-symbols A and B have identical functions. The only difference of course is the pin numbers. And, the third sub-symbol in both cases is the power block symbol - just consisting of Vcc and Gnd pins.
For ease of understanding I have added the screenshots of eeschma and symbol editor for the 74LS74 TTL device from KiCad lib as word file.
200121 KiCad Screenshots.docx (176.4 KB)
Looking forward to you help in understanding this.
Thanks and best regards