ASIair Plus TF port problem

stubblejumper

My SanDisk MicroSD card isn't recognized. I have pushed it in till it is almost flush with the body. If I shove it in any further I might not be able to pull it out. I am using the card orientation as shown in the image on the body right beside the port.

Any suggestions?

Kring

Ah, so this confirms you havn’t properly inserted it. (Asked on your other post) It should be completely invisible and sunk in, I had to use a fingernail to push it well beyond the case and have it audibly click in as inserted. It’s not like other SD cards that just slide in and sit there protruding a bit.

To get the card out, you need to eject it by using a fingernail to push it inward, then it will pop back out.

stubblejumper

OK. I wondered if it had the spring back feature but was worried that I'd be screwed if I pushed it fully in and no way to get it back out. Thx for the info.

The ZWO USB stick did a first rate job to transfer the data to my desktop. I want to use eMMC for the captures because it is so much faster than USB stick or MicroSD cards.

Don

Kring

If you are looking for speed - pickup a SanDisk Extreme Pro USB, does 420 mb/sec, and speeds up the whole imaging process including previews. Substantial faster than the eMMC, and it quicker back to your workstation. They are cheap and much larger. I think 256GB is like $60 in USD.

the copy function works great but there is one gotcha with it; it alters the files date stamp, so if you image over multiple night the dates all become the copy date - I find this is annoying to sort and filter out files.

and depending on your camera you can run out of storage pretty darn fast in eMMC, especially if you do a run of calibrations

w7ay

Kring SanDisk Extreme Pro USB, does 420 mb/sec

While the fast SanDisk is faster than the eMMC (even the best eMMC can only do 400 MB/sec, and who knows what eMMC ZWO uses in the ver 3 of ASIAIR), the external memory will be limited when transferring camera data to the storage.

The Raspberry Pi 4 has a single lane USB controller that is shared among the USB ports. The limit there is about 4 Gbps (about 500 MB/sec). So, the best transfer rate from the USB camera to the USB storage (USB bus shared between the two) would be around 250 MB/s.

FWIW, using fps data from the ASI482, I get about 270 MB/sec max camera transfer rate, so we are really pretty much limited by the camera, in any case.

Reading back ASIAIR storage to the computer is a different story. The external drive can make full use of that single lane, and a good USB drive (I use a Samsung T7 SSD drive) will beat out the fastest eMMC memory.

In any case, both a good external drive or the eMMC will be faster than either a microSD card (about 100 MB/sec) or a cheap USB 2 flash drive (about 60 MB/sec).

Since there is no speed disadvantage (and might be a big advantage depending on the eMMC speed ZWO chose to use), and the external storage size is virtually unlimited, a good external USB drive is better than the eMMC from a purely technical viewpoint. Cost is a different story -- a 2TB Samsung T7 SSD costs as much as an ASIAIR.

Chen