I've read this code directly from the Onkyo remote that came with the receiver.

0000 006C 0026 0000 0159 00AC 0015 0015 0015 0040 0015 0015 0015 0015 0015 0040 0015 0015 0015 0040 0015 0040 0015 0015 0015 0015 0015 0040 0015 0040 0015 0015 0015 0040 0015 0040 0015 0015 0015 0040 0015 0040 0015 0015 0015 0040 0015 0015 0015 0015 0015 0040 0015 0040 0015 0015 0015 0015 0015 0040 0015 0015 0015 0040 0015 0040 0015 0015 0015 0015 0015 05FB 0159 0057 0015 0E7C 0159 0057 0015 00AC

It seems to be the cleanest one of the dozen or so I captured on my Pronto NG.

It won't work when I load it into an iRule app (Kindle fire platform and iTach IP/IR converter) as a Pronto NG code.

Everything else works - the other Onkyo codes via IP, Roku, LG Player. Oppo player, ISY, etc., etc. I just can't use the iRule app to power on the receiver from full (not standby) power off.

I can't find this code in the RC database. Is it there, if so where?
If not, might it be possible for someone to check this out and clean it up?

What code is this? Like what is the function name? I have a pretty large db of confirmed integra/onkyo codes already generated into pronto hex we can x-reference against.

That learn decodes as 210.108 OBC 203, which is Power toggle as you can see from the Onkyo spreadsheets available at AWE Europe.  Use the TX-NR1010 - IR link to get the most recent spreadsheet.  Older Onkyo models are included. Column C gives the Pronto Hex for Zone 1.

Your learned code is not very good; it has th wrong repeat behavior and doesn't include a leadout.  Here's the Pronto Hex from the above spreadsheet:
0000 006D 0022 0002 0156 00AB 0015 0015 0015 003F 0015 0015 0015 0015 0015 003F 0015 0015 0015 003F 0015 003F 0015 0015 0015 0015 0015 003F 0015 003F 0015 0015 0015 003F 0015 003F 0015 0015 0015 003F 0015 003F 0015 0015 0015 003F 0015 0015 0015 0015 0015 003F 0015 003F 0015 0015 0015 0015 0015 003F 0015 0015 0015 003F 0015 003F 0015 0015 0015 0015 0015 05F6 0156 0055 0015 0E47

Thanks to you both.
My Onkyo receiver has a standby state and a power off state. If it is set up to go into network standby or certain HDMI pass-though modes, it goes into the standby state when I send the Power Off command from iRule.
If the receiver loses power, or it is powered off in certain HDMI pass-though modes, it goes into the power off state.
The power on codes supplied by iRule for the receiver turn it on if it is standby but not if it is in the power off state.
The Onkyo remote control sends an IR command (POWER) that turns the receiver on when it is in the power off state. This is the IR command that I tried to learn on my pronto and that 3FG has provided. iRule sent me three IR power codes identified as: Power On, Power Off and Power Toggle. The one 3FG has provided is the Power Toggle of those three. This makes sense, because the power key on the remote operates as a toggle switch.
So there should be an end in site. Unfortunately, so I haven't been able to get that code to work on the iRule.
If SysIntegration has other codes I could try, I will do that. Other than that, I'll continue to bug the (very patient and helpful) iRule online help guy.

Just to wrap up.
iRule architecture assigns one gateway (basically an IP address) to each device (set of commands for a piece of equipment). Each gateway will only support one mode of communication - basically IP or IR. My requirement meant using both IP and IR to communicate to one device (my receiver). I therefore had to set up a second device to handle the IR command (iRule now thinks my receiver is two devices) and assign an IR gateway to it. It would seem that this is not often done in the world of iRule.
Having confidence that I had the correct IR code helped a lot in uncovering the underlying issue.
More detail in my post "Onkyo Power On" in the iRule forum.
This question is closed. Thanks again guys.

That link is now dead...anyone have a copy of this onkyo spreadsheet saved they would send me? I have an older one, but I have a couple of commands in mine that are giving me issues.

Nevermind found one. anyone else looking try here:

https://openremote.github.io/archive-dotorg/forums/22874433.html