Other SATA/ATAPI devices (like BDROM drive) support

[n4us]

Issue Type

Request

Description

I was wondering if it'd be possible to use pydiskcmd to talk to other SATA devices (like a DVD drive) like this: https://www.farnell.com/datasheets/1812959.pdf

It seems to support the following standard ATA commands:

[jackeichen]

Thanks for your issue, this should be a feature request.

It is not very hard to add the support for other SATA devices, but:

1. it need some time to read the spec, and
2. need a device like you said(I have no DVD drive on hand).

I think we will finally finish it if you could collaborate with me.

[n4us]

Hello @jackeichen thanks for the quick response.
There are a few different standards/specs that we would need to collect and read.

I'm happy to collaborate with you, I have a few DVD drives and similar devices at hand. Please let me know how to proceed,

Thank you

[jackeichen]

Hi @n4us ,

1. Firstly, we should clarify what the difference is in the standards/specs(could you share it with me?), and the scope of the feature(what OS to support, Linux or Windows?);
2. In the next step, we will try to develop the feature and implement at least one command, and test it with your DVD drives;
3. Finally, we will implement all the commands that you need.

[n4us]

Hi @jackeichen

1. This page seems to explain the specs well: https://wiki.osdev.org/ATAPI , basically ATAPI seems to support mostly all of SCSI commands, plus a very few ATA commands.

2. Important commands seem to be the following:

• INQUIRY 0x12
• MODE SELECT 0x55
• MODE SENSE 0x5A

Inquiry is the most basic command to get drive serial number, firmware info, etc. All the other standard commands in the page are important as well. But Mode Select and Mode Sense can be used by vendors to implement custom commands, so they are important. I don't yet understand fully the "sense" related concepts or naming, but seems to be important.

• START STOP UNIT (Eject device) 0x1B

This can be also useful and easy to test if it works.

Thanks

[jackeichen]

@n4us Most of the commands should be supported in the low level component, including Inquiry/Mode Select/Mode Sense/Start Stop Unit, so nothing to do in this section.

Then go to next step. What kind of device path name string of your device, like /dev/sdX or /dev/sgX in Linux. Only /dev/sdX is handled for now in pydiskcmd. We may need some little change if you want sgX.

If you get smartmontools in your OS, please show your information:

# smartctl --scan
# smartctl -a /dev/<your-DVD-device>

[n4us]

@n4us Most of the commands should be supported in the low level component, including Inquiry/Mode Select/Mode Sense/Start Stop Unit, so nothing to do in this section.

Then go to next step. What kind of device path name string of your device, like /dev/sdX or /dev/sgX in Linux. Only /dev/sdX is handled for now in pydiskcmd. We may need some little change if you want sgX.

If you get smartmontools in your OS, please show your information:

# smartctl --scan
# smartctl -a /dev/<your-DVD-device>

@jackeichen Great! Could we get an example in https://github.com/jackeichen/pydiskcmd/tree/main/examples for how to use inquiry, for instance?

I will need to check, as I have been using Win11 for now for this purpose. In fact, it would be interesting to figure out what is the "absolute path" of the device in windows (I don't refer to the E:\ filesystem path, but the internal ones that look like \\\\.\\PhysicalDrive0)
What are the differences between sdX and sgX devices on Linux? I will try to see how different SATA DVD drives get recognized.

[jackeichen]

@n4us the example is added in https://github.com/jackeichen/pydiskcmd/tree/pydiskcmd-dvd-drive/examples

win_scan_device.py

# python win_scan_device.py

This will scan all the device in your windows. You may search the device Win32 Device Namespaces string that starts with "cd" or "dvd". My cd device is usually \.\CdRom0.

If you want to find out the DVD drive, you may get all device with win_scan_device.py, then disable the DVD drive device and get all device again, to find out the difference.

inquiry.py

python inquiry.py \\.\<your-dvd-device>

After find out the device name, you can send inquiry standard command with this script.

To simple the process, we could ignore Linux(sdX and sgX is Linux device path format) and focus it on your win11.

[n4us]

@n4us the example is added in https://github.com/jackeichen/pydiskcmd/tree/pydiskcmd-dvd-drive/examples

win_scan_device.py

# python win_scan_device.py

This will scan all the device in your windows. You may search the device Win32 Device Namespaces string that starts with "cd" or "dvd". My cd device is usually .\CdRom0.

If you want to find out the DVD drive, you may get all device with win_scan_device.py, then disable the DVD drive device and get all device again, to find out the difference.

inquiry.py

python inquiry.py \\.\<your-dvd-device>

After find out the device name, you can send inquiry standard command with this script.

To simple the process, we could ignore Linux(sdX and sgX is Linux device path format) and focus it on your win11.

Hi @jackeichen

ACK, thanks a lot. I will try it later this week, and report what I see and can play with on the weekend.
Thanks again!

[jackeichen]

Waitting the answer.