With the help of the community we’ll get it working. The PCB is the easy part, atleast for me. Harder part will be the code but I know there’s more than enough knowledge in here! Obviously the final schematic/pin mapping will be shared in this...
Done on my custom board that uses the small PSRAM footprints as the space is limited. At 133MHz FlexSPI with two PSRAMS only 8MByte is registered with the test sketch you made. If I lower to 120MHz then 16MByte shows up.
You’re right. I’m sorry if the two threads are confusing. The purpose with this one is to have the community together make SDRAM possible for the Teensy. Just like so many other threads where everyone’s come together to make things happen...
One thing I noticed when going from 1x 8MByte PSRAM to 2x, is that I could no longer achieve 133MHz speed. I had to go down and the highest I found was 120MHz. It doesn't matter much to me when it comes to that. But one APS12808 is one less...
Yes but that's both a cost and extra logistics. Not ideal and thus why I'm trying to look for other solutions.
Good to know as a worst case.
I'm working in parallel to try to get Mouser to ship to China. We'll see how that goes.
If you say that the pins look good then that's enough safety for me to order the board.
I'll update this thread in 2ish weeks time once the board arrives.
Hello fellow Teensiers.
First off, this is only for custom boards!
I plan to make the Teensy work with SDRAM. Making custom Teensy boards is something I've done for a while with great success. The forum has been good help and the community we...
Thank you Paul for taking the time. They seem quite different after all. I found the chip by using Mousers filtering and so I filtered to the same specs as the ordinary PSRAM's to try to find alternatives. There really isn't much to choose from...
There are 16 MByte chips that are still 8 bit, but different footprint. Looking at the datasheet tho, it looks like they need 8 datalines(?)
But looking at the facts, it's the exact same as the 8 MByte ordinary PSRAM's. Meaning 3V, 133mhz, 8bit...
Sounds good Joe!
I use the standard simple example like this:
This code above and outside setup()
This code in the start of Setup to make sure it's always first. 2 seconds is good for me.
Then obviously the feed function
In my loop, alltho...
I solved it by doing this. I give the flash_move function the name of my watchdog feed function. It worked perfectly now that I tested it.
Question remains, is this considered safe(?). Because if flash_move fails for some reason, the dog will...
Calling directly feed() is ugly just as you say.
I'm gonna do my best to add code to the flash_move which feeds the dog.
I think it could actually be a good addition to the library. Adding a #define and #ifdef, so that if someone has a watchdog...
It would be very nice if there was a disable option. For example in my case, I have OTA on the Teensy using FlasherX, but when the move occurs, the watchdog will trigger and thus brick the device by restarting.
I've tried to use
I have a scenario where I need to stop the watchdog when doing OTA otherwise it will restart the device which bricks it in this case.
Is there a way to disable the watchdog once it's been configured?
SOLVED!
Solution: 1x PSRAM works fine with 132mhz FlexSPI, but when having 2 of them, only one seems to work.
I dropped the mhz down to 88mhz and that made the test sketch register 16mb. Time to play around and find the fastest speed it'll play...
Footprint of these are tiny, will take time to solder them onto a 4.1. But that will ofc be my last resort to verify. And it's leaning towards that.
Atleast now I got confirmation that it should just work. Thanks Paul and good work on the new...
That's good to know atleast!
In other words, my schematic is correct since it's copied straight of the 4.1. And the APS6404L-3SQR-ZR works fine as a single (8mb) PSRAM, it should then also work in a pair?
What would you try next?
I'm running the test sketch that Paul has linked here: https://www.pjrc.com/store/psram.html
The sketch shows 8mb but I have 2x PSRAM's on the board.
From what I understand having 2 PSRAM's should just work automatically(?)
I've double checked...