Picade setup

Ive got my picade and was lead to belive by piggy backing it on my pi it would take its power from the pi - this is not working for me - do i need to add any leads, power thru cables etc?

PiCade Hat? https://pinout.xyz/pinout/picade_hat#

Aye, thats the one - Pins 1 and 2 are the 3.3 and 5v however my picade hat doesnt get any power…
:(

You shouldn’t need to do anything special to get power to it. Do you have a voltmeter to check the pins for power?
What model Pi are you using and how many Amps is your power supply rated for?

Pi 3 b - going to upgrade it to the very latest one this week to see if that will help
power supply is a standard pi power supply. works for every other pi i have (I run a weather station and flight tracking station)

I will get a new PSU as well. :)

I recommend getting a good quality 2.5A (or better) power supply for the 3B+.

Well i got a new 2.5A PSU - no go. I still cant even get the pi without the picade hat to boot.
Will 3A be enough or should I go higher?

2.5A should be more than enough to drive a Pi 3B or even a 3B+ by itself. The 3B only draws ~400ma idle current. A 3B+ will be slightly more than that. It sounds like you have an issue with your Pi. If its a 3B+ make sure you have the latest version Raspbian. Any indicators lite like the Red Power Led?

yes - the red power light flashes, the screen has the multicoloured square and the powre lightning flash

Very latest Raspbian? 2018-04-18 Kernel 4.14?

it probbaly wasnt as i was trying to build a picade so wanted an image that would be useful for that - current wresting with reformatting my sd card and installing the latest rasbian

Doing a sudo apt-get update, sudo apt-get upgrade from a 3B or earlier Pi, should make the SD card bootable / usable on a 3B+.

lol - well latest raspbian working fine - of course it doesnt come with an onscreen kb so i have to go find one - to install one from the point and click requires password input - which requires a keyboard that i dont have yet.
SO silly of them not to have an onscreen kb by default - so i can type in the network password.

Still cant see if the pihat is working as it doesnt have any LEDs on it to indicate it works.

Yeah, each new Pi requires new boot code to be added to Raspbian. Which means it will only boot with the latest Raspbian. You can upgrade and then move your card. It works most times. There was also an issue with false under volt indications on the 3B+ that was patched.
I don’t own a picade so I can’t help you much with that, other than the basic stuff you do to see if any hat is working. If it used i2c running i2cdetect should show you what i2c address are in use. I believe the command to run from terminal is sudo i2cdetect -y 1