I would be very surprised. I have been wrong before.

Well. Unless someone is going to

(1) post an actual protocol sheet
(2) tell me where they got this TV ( I am guessing Blue Box)
(3) post some learns from the OEM remote in hex (or any other control system file format)

then I don't know how to help.

Its remote doesn't look like a Sharp I have seen, but I don't have access to it to see what's going on underneath or in the code...... anyone want to help us help you? :-)

Thanks. I appreciate the effort. Don't know if it helps but these are the only codes that I can find that work with this TV:

Power Toggle:
0000 006C 0000 0020 000A 0047 000A 001E 000A 001E 000A 001E 000A 001E 000A 001E 000A 0047 000A 0047 000A 001E 000A 0047 000A 001E 000A 001E 000A 001E 000A 0047 000A 001E 000A 06DC 000A 0047 000A 001E 000A 001E 000A 001E 000A 001E 000A 0047 000A 001E 000A 001E 000A 0047 000A 001E 000A 0047 000A 0047 000A 0047 000A 001E 000A 0047 000A 06DC

Volume Down:
0000 006C 0000 0020 000A 0047 000A 001E 000A 001E 000A 001E 000A 001E 000A 0047 000A 001E 000A 0047 000A 001E 000A 0047 000A 001E 000A 001E 000A 001E 000A 0047 000A 001E 000A 06DC 000A 0047 000A 001E 000A 001E 000A 001E 000A 001E 000A 001E 000A 0047 000A 001E 000A 0047 000A 001E 000A 0047 000A 0047 000A 0047 000A 001E 000A 0047 000A 06DC

Volume Up:
0000 006C 0000 0020 000A 0047 000A 001E 000A 001E 000A 001E 000A 001E 000A 001E 000A 001E 000A 0047 000A 001E 000A 0047 000A 001E 000A 001E 000A 001E 000A 0047 000A 001E 000A 06E5 000A 0047 000A 001E 000A 001E 000A 001E 000A 001E 000A 0047 000A 0047 000A 001E 000A 0047 000A 001E 000A 0047 000A 0047 000A 0047 000A 001E 000A 0047 000A 06E5

Alright. This is going to get a little confusing, partially because my own plethora of posts, but maybe I can clean it up.

The codes posted above are Sharp protocol device=1.
The majority of sharp discretes I have posted regarding modern Sharp TVs are Sharp protocol device=17.

(If you're lost. Download IRScrutinizer from JP1 forum and copy/paste. The program does the hard work for you). Even going back and looking at my own old posts for the LE550/650 series TVs, the only thing that these TV's responded to were codes that were Sharp protocol device=1. I did these code exploration without OEM remotes and working from the knowledge that the higher end sharps responded to codes listed above. I also learned codes from the OEM from the high sharp's to confirm d=17. I have not have access to the OEM for these lower modeled TVs, though I have been sent a small sample of learn codes that all show d=1. The next step is to generate the full code set for THIS device protocol set and fire them at the Sharp LE550/650 models.

I think I've found something, but I need someone to test it on some Sharp models that I don't have regular access to.

I have a 70LE550, desperatly need discrete codes for power. I have a harmony 650 and just picked up a JP1.3 comcast remote. I have a serial-USB cable I can modify. I have lots of linux and windows experience, but I haven't done much remote programming before.. but I would love to help.

You can try any Sharp device code by using the following range of EFCs
Device 17: 43264 to 43519
Device   1: 59648 to 59903
To test these manually, first assign setup code 11602 to the TV button.  Then each of the 256 EFCs for either device can be tested by tapping Setup (don't hold it, and entering in the 5 digit EFC. When you press the 5th digit, the remote will send the IR signal.  Make sure that the procedure is clear by trying this first with EFC 59730, which should send Power toggle.

If you arrange your USB to serial converter to connect to the Comcast, it will easier to try since you can load up 100 or so EFCs at a time, assigning each to a unique button (using both TV and AUX)  and test them by just pressing each button.  If you plan to do that, check to see if the converter uses a FTDI chipset.  If it instead uses a Prolific or Tiao chipset, use the 983 command to blink back the remote signature.  If it is 3039, no problem.  25562 is a JP2 remote and won't work with a Prolific chipset. 

Assuming you have tried the power commands from the two links in post #2. I have fired all 510 commands (Sharp protocol d=1/d=17) at the LE550 (and 643) series and have yet to find discrete power. I think one of my links above mentions that.

If you find anything that works other than a power sensor, let me know. I've put a great deal of time into it, but I think Sharp just dropped the ball with that series line.

I don't yet have a way to try pronto codes, I ordered a jp1.3 cable, as I see that it is more than a cable modification.

I do have and android tablet with an IR port, so I can try codes with that... is there a recommended app for that?

I did see your other post concluding that there were not discrete codes for the LE550, but I was hoping that another set of sharp codes would work.

I'm sure some of the other sub forums can help you find an android app or even a search of your favorite search engine.

I am hoping there is another set of sharp codes that would work to. I do not think that there are. Learning from a sharp oem remote, we find that there are two sets of sharp codes it shoots out, Sharp d=1 and Sharp d=17. I've personally gone through both Code sets for a 550 series TV. (Personally, I am grateful that we don't carry that series line).

The Sharp protocol has 32 code sets (0-31) with 255 available codes for each one. (Quick math ~8000 codes). Personally, I'd rather use a power sensor or trigger or something. There is definitely not enough time to go through 8000 codes for an entry level TV, I'm sorry to say. Maybe, though, this post will "flashmob" the internet and all code sets will be checked against this TV series line. Trying 500 codes against 15 TVs is enough for me. I hope I am wrong and discretes exist. I am ridiculously skeptical.

I just bought it for its glorious 70 inches, "How shitty could the rest of it be?". Well anyway, I am sufficiently nerdy/ocd that I might just learn enough jp1 too to try this out. I'll bug sharp support too, but I'm sure that will not help.

Thanks for the pointers, I'll certainly report back should I find results positive or negative.

Well...I was NOT!!! able to find discrete codes for this Sharp HDTV set....I was however able to use an "anchor" command followed by a toggle in a macro to simulate discrete input and it works pretty well....Still no power discrete though....just power toggle....oh well...

I ream'ed Sharp tech about this and they were fairly understanding and apologetic.....Maybe they will do a "firm-up" that will correct the problem....I am confident it is a software/firmware issue and not a hardware issue..it can be corrected...and with any luck....it will be....
Installers beware!!!...Sharp is not including discrete codes in all there HDTV's....and as any pro installer knows...this can be a BITCH!!!

Thanks for all the responses and suggested code sets/hex (which didn't work BTW....but Thanks just the same....)