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Cameo/Aphid benchmarking

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Lisa2:
So I finally was able to put together a Cameo/Aphid device to play with. I was interested in the performance of the Cameo/Aphid vs. the X/Profile.  My test setup is a 2/10 running MW+II with an X/Profile in place of the Widget,  the Cameo/Aphid connected to a dual parallel port card, and a PCMCIA flash drive connected to a Sun SCSI card.  To test the performance of the drives I used an old HD benchmarking program from LaCie named TimeDrive.  This program does non-destructive testing using the driver ( not direct SCSI calls) so it's a good fit for these parallel port drives.  A made a quick video of the testing ( that my cat photo-bombed ), it's boring, shaky, and about 5 min. long, but for those who may be interested here is the link:

https://youtu.be/pDfxcUbvBc0

The test is not scientific, but the results were interesting.

Rick

stepleton:
Wow, cool! Maybe I shouldn't write hard drive emulators in Python :-)

It would be nice to compare two drives on the same port; it's possible that the internal port and the expansion card could have different rates. Another factor might be the SD card in use inside the Aphid (as well as the media in the other devices). Most SD cards will be plenty quick, but the speed difference between an older Class 4 device and a Class 10 or better will likely be substantial in Cameo/Aphid.

One slightly obnoxious quirk of the internal I/O mechanisms that Cameo/Aphid uses is that data has to be passed around in 512-byte blocks. As a ProFile drive block is 532 bytes, you need two of these transfer operations to access a single block. If you wanted to, you could write these blocks directly to shared memory inside the PocketBeagle, but I chose the path of purity...

I wonder how a real drive would do!

Lisa2:
A couple more quick notes on this:

1. I was using using the latest build of the Aphid software from this summer.

2. I think the SD card used in the Aphid is a class 10 ( I will confirm this later ).

3. The CF card in the X/Profile rated at 80x speed ( 80 x 150 kB = 12,000 kB or 12Mb ?? )

4. I did try connecting the Aphid to the internal port on the 2/10 without success so far ( I do have the correct cable for this ), but I can try the test again using both connected the dual par port card ( or to the same exact port if you want ).

5. I can also run the same test on a real profile or a widget if you want, I have both working available. 

Rick

blusnowkitty:

--- Quote from: stepleton on September 08, 2021, 01:45:00 pm ---It would be nice to compare two drives on the same port; it's possible that the internal port and the expansion card could have different rates.

--- End quote ---

For what it's worth, I found this in the Parallel Card manual trying to debug my homemade DMP cable:


--- Quote ---1. Timing. The Lisa parallel connector is driven by a 500 kHz clock. The Parallel Interface Card supports a faster clock operating at 1.25 M Hz. This affects software using 6522A internal timers.
--- End quote ---

https://generalphiles.com/files/Apple/Lisa/Parallel%20Interface%20Card.pdf
Page 14, or PDF page 21

Lisa2:
This would seem to indicate that the Dual Parallel card is more than twice as fast as the internal port.  I am not sure this is case.  The Dual Parallel card manual also states the card has a "625K bytes/second maximum data transfer rate", I can't find this spec for the internal port right now.

I can test the same X/Profile on the Dual Parallel card and see if it's any faster... ;)

Rick

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