The device here is CF card, converter makes sure this pin is ATA1 compliant so the device can successfully initialize as Master.

The device is what's controller sees on the cable. Converter is a bridge between the device interface and the device implementation, it is a device from the IDE controller's point of view, and must behave as a device. I've checked with ATA1, the only time when the device can drive that line on the cable - is when it is configured to output "Spindle Synchronization", all the other uses are inputs.

The converter can do whatever CF needs on the PCB, but not drive the cable line on behalf of the controller.
Moreover, the signal from pin 28 does not go anywhere on the PCB. Whatever CF needed for initialization - this had nothing to do with pin 28. The pin just sits there, in a row of GND's, not being connected to CF card at all. Cutting that pin from the ground on the connector and not losing CF functionality just proves the converter does not make use of that pin in any way.

Of course converter doesnt use that pin, but according to ATA1 that pin is no longer BALE, its CABLE SELECT.

You're ignoring the point - the CABLE SELECT is something that gets driven by the controller side of the cable, or by the cable. There is absolutely no point in driving cable select from the device side of the connection, and doing so contradicts the ATA1 specification - the device only listens for cable select from the cable, never drives it. The converter does not follow ATA1, it violates it.

CABLE SELECT is either already connected to ground or floating (assuming the CF adapter is connected to a CS compatible cable and not the controller's pins directly), grounding it isn't going to matter.

vstrakh wrote on 2023-03-15, 07:36:

The device is what's controller sees on the cable. Converter is a bridge between the device interface and the device implementation, it is a device from the IDE controller's point of view, and must behave as a device. I've checked with ATA1, the only time when the device can drive that line on the cable - is when it is configured to output "Spindle Synchronization", all the other uses are inputs.

I would not use the word”Bridge” here. When speaking about computing and networking, a bridge does 2 way conversion. In this case, the CF is a native PATA IDE device and the adapter doesn’t do any conversation. The 40pin to CF adapters is no more a bridge than a 40pin ide to 44pin ide adapter. It’s just 44 wires and maybe a voltage regulator.

If you look at a CF pin out, you will see that it has all the same pins as an IDE cable.
https://allpinouts.org/pinouts/connectors/mem … y/compactflash/