Hello. I’m using 1.2.40 to capture data that’s imprinted on an HP 41 calculator type tape used in an old CNC machine. I have managed to get this BiPhase data RAW into a spread sheet when its being transmitted from a PC to the tape system using Logic 1. Data looks good and steady on a scope and coming at 5kcycles/sec and I get a clean capture of 200 secs of data at 2MS/s.
However, when trying to capture similar data coming from the tape drive to the machine or PC, the timing interval isn’t so precise, maybe a 10% variation, and Logic 1 complains about sample rate needing to be lower, so it gets changed to 1MS/s, and the system simply cannot deal with that and changes it it back again to 2 where upon it fails all over.
Is there a way I might overcome this? I only want to do it once to preserve precious data on a special tape.
@rjs.russell Sorry for the trouble you’re running into.
The error could be due to a time measurement error due to a slow sampling rate when compared to the frequency of the signal:
What frequency is the data coming from the tape driver? Are you able to share a .logicdata capture file with me?
The most common causes for this error are described below:
However, I’m surprised you’re running into the error at only 2 MS/s. Which specific Saleae Logic model do you own? You can refer to the Logic models listed below for reference:
Hi Tim,
Attached is the data I successfully captured, but from a tape emulator, not an actual tape.
I needed to do this to understand how the data is formatted (BiPhase without any stops or checking), just a constant stream.
The Logic application also required with the emulator stream that the sample rate was 2M before I got a successful save of the whole stream.
Just to add to my confusion, the tape drive has gone on strike today and ceased functioning. It did this once before, and magically came back to life, so I cannot have another go at saving a file today, unless that is stored on the laptop without my specifically saving it. The host laptop is a Dell running Windows Vista, so may not have the fastest USB ports.
I have to confess that my analyser, says Saleae 24Mhz, 8 channel upon it, but probably not actually been manufactured by yourselves having compared it with your images. So I guess my question is outside your brief.
Rupert
(Attachment 2 MHzTape.7z is missing)
Hi Tim,
Attached is the data I successfully captured, but from a tape emulator, not an actual tape.
I needed to do this to understand how the data is formatted (BiPhase without any stops or checking), just a constant stream.
The Logic application also required with the emulator stream that the sample rate was 2M before I got a successful save of the whole stream.
Just to add to my confusion, the tape drive has gone on strike today and ceased functioning. It did this once before, and magically came back to life, so I cannot have another go at saving a file today, unless that is stored on the laptop without my specifically saving it. The host laptop is a Dell running Windows Vista, so may not have the fastest USB ports.
I have to confess that my analyser, says Saleae 24Mhz, 8 channel upon it, but probably not actually been manufactured by yourselves having compared it with your images. So I guess my question is outside your brief.
Rupert
(Attachment 2 MHz, 400 M Samples [4].logicdata is missing)
Hi Tim,
(I cannot get an attached logicdata file raw or zipped to be accepted by your system so this is sent without )
Attached is the data I successfully captured, but from a tape emulator, not an actual tape.
I needed to do this to understand how the data is formatted (BiPhase without any stops or checking), just a constant stream.
The Logic application also required with the emulator stream that the sample rate was 2M before I got a successful save of the whole stream.
Just to add to my confusion, the tape drive has gone on strike today and ceased functioning. It did this once before, and magically came back to life, so I cannot have another go at saving a file today, unless that is stored on the laptop without my specifically saving it. The host laptop is a Dell running Windows Vista, so may not have the fastest USB ports.
I have to confess that my analyser, says Saleae 24Mhz, 8 channel upon it, but probably not actually been manufactured by yourselves having compared it with your images. So I guess my question is outside your brief.
Rupert
@rjs.russell Ah, thanks for clarifying that. Apologies we’re unable to help debug these timing issues for you since it’s not one of our official devices.