Circuit Logistics question

[LittleMikey]

Hi guys,
So while I'm not new to Factorio, I've never used the circuit/logistics system to much effect. Does anyone know any good tutorials online?

Currently I am trying to do two things:

1. Make a requester chest that requests the specific research packs for the technology I am researching. (Like if I'm researching a red and green tech it would request red and green science packs).
   Not sure if this is possible, but it'd be cool.
2. I've got an assembler producing barrels, but I don't want it to just keep producing barrels forever. Is there some way to stop it after producing a certain amount? I know I can limit the stack size of a chest, but the barrels are getting shipped out to various locations all around the map so setting a limit on a single chest won't do anything until the system is completely full of thousands of barrels.

Thanks for helping!

[leitk]

1: as far as I know, there is no way for a circuit to know what you are researching. You could see that some beakers are being used and others are not and shut down that part of the factory. But in general, just limit your chest size and let it fill up, you'll use it soon enough.

2: I would also let barrels stop by filling up. Put your barrel making assembler on the line with barrels, if it's full, it won't make more.
If you really want to set a maximum, you could hook a counter to the inserter with read pulse taking things out of the assembler and turn it off if over a maximum, or if the rest of your factory is running low.
counter is output hooked to input. Either type should work in this case, comparison could reset it. addition should be + 0 (or x 1).

Some things I did recently with circuits:
Unloading two things from a train into one chest, without the stack inserter getting stuck or unloading too much.
Keeping train unloading even.
No delay between one train leaving a station and the on deck train starting to enter.

[mrvn]

To limit the number of barrels overall you have to either count them as you produce them or connect every chest that can have barrels into a single circuit network. Then you can simply set the inserter to barrels < 10000.

This is usually quite impractical. But when you have researched roboports you can connect the inserter to the logistics network wirelessly. You then can control the inserter by how many barrels are in all logistic chests within your logistics network. Works great if you plan to transport your barrels by logistics robots.

[torne]

https://mods.factorio.com/mods/justaran ... combinator will output the requirements of the current research to the circuit network.