Factorio Forums

I was trying to make a latch to launch 1 silo then the other, by reading contents and launching when science packs hit 1000
However, on a seemingly random basis, one silo or the other would not output 1000 before launching and instead output 992 for example, then 0 on the next tick.
This resulted in my latch never swapping

I expect to be able to read the exact moment a rocket launches, but this makes that unreliable hence the bug report.

I tested with common and legendary silos, both have same issue. It happens frequent enough that you should witness it in the save file in under a minute

Example shown here - https://youtu.be/xzoT_oOoqME
Video is from a modded save, but I replicated same issues on an unmodded editor save which has been attached below v

Save file - https://drive.google.com/file/d/1oD_ZGR ... drive_link

This forum post reported the same behaviour in 2.1.19, and was allegedly fixed for 2.1.20 but I am still experiencing the old behaviour - viewtopic.php?t=136185

Hm... i see the exact case that i missed. When implementing 136185 i focused a little bit too much on what was reported (launching starter packs) but forgot that items can also be launched because of orbital logistics (space platform requesting items) and transitional requests (when silo gets requests set dynamically). The way i implemented it means that rocket silo behavior sends cargo pod item counts for 1 tick after items were moved from rocket silo's inventory into the cargo pod inventory as part of the launch, but the orbital logistics moves those items on its own somewhere else and then asks the silo to launch without doing this transfer from silo to cargo pod thus skipping this 1 tick signals transfer. This raises quite important question about the feature: what should happen when a silo is launched such that only some items are moved from a silo into the cargo unit: should the 1 tick output contain just the cargo unit content because this is what is being sent, or should it contain cargo unit and rocket silo content because not all items were put into the cargo pod.

Ok, i hope this is now completly fixed for 2.1.21. As for the content sent to circuit network i decided that it should contain both rocket silo and cargo pod content in case the rocket launched contains only a few items as if only cargo pod was included the value transmitted would jump like 1000 one tick, 10 next tick and then 990 a third tick just because in the middle it was sending cargo pod content excluding rocket silo.