Minecraft Command Block Item Enter Spawn command?

Hi, would like to build a Minecraft bedwarsmap. Have only one problem and although I do not know how to set this in a Commandblock that at a distance of 30 seconds z.b. Diamonds are talked about.

Does anyone know how this works?

/ summon Item ~~~ {Item: {id: "minecraft: diamond", Count: 1}} [https://www.minecraftforum.net/forums/minecraft-java-edition/redstone-discussion-and/commands-command-blocks-and/2507738-spawning-dropped-items]

I hope this helps you.

Of course you have to replace the Tilden with your desired coordinates

or you write the relative coordinates behind the tildes.

For the 30 seconds you need a clock (Redstone or Commandblock)

Or you can do that with the commandblocks and switch to spigot plugins. https://www.spigotmc.org/...uildtools/

Where I learned how to write spigot plugins with eclipse in Java:

https://www.youtube.com/...Y9TQ4XlmmA

All right.