View Full Version : Allocating memory for Maximum delay...

03-16-2016, 04:38 AM
I'm out for maximum delay available -- I have memory added to the audio board & also franks memory boars, which is fully populated.
My understanding is that using

AudioEffectDelayExternal dly1(AUDIO_MEMORY_23LC1024)

should allocate 'all memory'.
But some forum post I read (can't find it now) suggested that I cannot allocate the delay all in one block?Do I need to daisy chain multiple delay objects? (One for each memory chip?)

Has anyone used Kris' (PeskyProducts/OneHorse) memory board (https://www.tindie.com/products/onehorse/spi-flash-memory-add-ons-for-teensy-3x/?pt=full_prod_search) with the audio board? Or is too slow being flash memory?
If his memory is fastenough, same basic rules from the audio product page? No problems stacking in any order?, or need to follow the general warnings for mentioned on the audio product page (https://www.pjrc.com/store/display_ili9341_touch.html) down lower "Usage With Audio Board Connections"

Just want to be sure information is still current, forum information has a tendency to be come the "authorative answer" but in time, it becomes wronng and is not corrected..,

shameless plug: oshpark sends 3 of everything, so I usually do then all to work on skills I have 2 more memory boars (sans memory as you can use flash or ram and not fill the board which adds to cost... If anyone needs one I can order the parts & send you a bill; or you can order the parts and send it here; I'll put together and get it out in the mail for $5 or 6 with tracking (no profit to me unless you an to buy me a beer for being a nice guy). Same deal I have 1 (maybe 2) ili3940 board display and the adapter for the touch screen version -- I have the boards assembled if you want teensy soldered on OR add a screen, that'd be extra too.====== that'd be extra; but again; not asking for money, just a thanks.
I can get the parts & add it to shipping cost or you can get the parts & ship to me. I love doing little one offs like this; I'm really getting into tiny smt soldering; almost zen like now. I digress; time for bed.

03-16-2016, 08:23 AM
The longest audio delays are possible with Frank's 6-chip memoryboard, populated with six 23LC1024 chips.

This will create a delay which uses all 6 chips:

AudioEffectDelayExternal dly1(AUDIO_MEMORY_MEMORYBOARD)

Detailed documentation is here:

Currently there is no software support for using 7 chips in a single delay object. You could possibly create 2 separate objects (6 chips and 1 chip) and wire them in tandem.

Flash memory chips are not suitable for real-time audio delays.

I am curious what you're actually *doing* with such a long audio delay?

03-16-2016, 03:12 PM
Thanks Paul. that explains why I wasn't getting the memory I thought I should get...I think creating two delay objects will be not worth the effort in this case. I may swap out the onboard memory chip for flash memory to store a start up/shutdown sound.
I have bad hearing, but use my ham radio often. I am always hitting "replay" on the Tivo (replay last 15 seconds so you can hear/see what just happened) -- On the radio, it's bad form to ask "What did you say?" so if I had a box I could just hit a button and it could repeat the last few seconds (I'll take as much as I can get, but wanted 15-30 seconds).
I also have kris' 1 gig memory addon board, but haven't figured out if that can be used yet. I am suspecting the speed will be more of an issue.
Another thought: can one stack two of franks memory boards?
Thank you.