My humble apologies if this is a answered elsewhere, but this is my problem:
I have a BRAT with a SSC-32 V2 (Atmege168). I am using VMware Fusion (a windows emulator) on a Mac, running Windows XP SP 2 on a MacBook Pro. I connect to the SSC-32 using a KeySpan USB to serial adaptor USA 19HS.
Now before you say “I have no idea what the hell to say about Macs, please go get a PC…” let me tell you this:
I can get LynxTerm v1.07 to connect to my SSC-32 and it will do basic things like command different servos on my BRAT to move this way and that. All-1500 works, etc. And while I am connected (using COM3 from the KeySpan adapter at 115k, with the usual settings) I can see from the KeySpan assistant that the port is busy. When I quit LynxTerm the Keyspan assistant says the com port is Idle.
BUT… when I quit LynxTerm, restart the power on on the SSC-32, and run visual sequencer 1.16, I cannot get this same set up to connect. I restart the SSC-32 and I get a steady green power light, but the VS cannot connect. Very frustrating.
My SSC-32 has the 2-01GP_beta1 firmware loaded and that was working just fine when I was using a REAL PC, but I would like to use my Mac as the PC is dead.
Can anyone shed light on my problem? It seems that LynxTerm has much more reliable connection to the SSC-32 than VS does? Is there a standard trick on windows to get this to work?
I believe you will find that seq is much more demanding of the serial connection than lynxterm with regards to timing. lynxterm is much like a common terminal emulator with some extra features and macro support geared specifically to making it easier to test out the ssc-32 and servos prior to using a more sophisticated app like seq.
I will also mention that not all USB to serial adaptors, and probably just as importantly their drivers, are created equal.
Moving forward though, if you had the particular usb to serial converter working previously under seq witha normal PC then I would strongly recommend looking to see if there is a setting to control latency and/or buffer timeouts in the driver. For some usb to serial devices this is located in the device manager dialog for the com port, sometimes under an “advanced” settings type button. Lastly, and not really knowing how much hardware abstraction the VMware software is having to do to get win xp pro to run on your mac, I also want to suggest there may be tuning parameters setup for that emulation that allow you to impact I/O legacy for the USB devices as well.
EddieB’s comment are dead on. However he didn’t mention that SEQ also has a timeouts screen that allows fine tuning of how SEQ handles the serial connection. I don’t know if it can overcome other potential timing issues with the emulator.
Thanks for your help. After poking around on the VMWare forums and elsewhere I decided to get a different USB <=> RS-232 adapter instead of my old KeySpan adapter. It would appear that there are many of these, but the key is to get one that has the Prolific IC PL-2303 chip set. I got mine here: sparkfun.com/commerce/product_info.php?products_id=8580
Using this adapter, the Visual Sequencer 1.16 connects just fine with SSC-32 from my MacBook Pro running VMWare 1.1.3 on OS X 10.5.4. My VMWare partition is running Windows XP Pro SP2.
This adapter also has drivers for Windows and Linux.
