Windows USB Serial driver .INF

[keeree]

(Crosspost from comp.sys.hp48)



I recently was digging around with my new HP 50g, and bemoaned the lack of Windows drivers for native serial over USB. It seemed rather silly that Mac OS and Linux could use it as a serial device, but there was no way to do the same over the basic USB cable.

After sniffing the USB packet information, and seeing it's basically just serial inside the USB protocol, I decided to try and force Windows to use the generic USB serial device drivers built into the OS. I didn't expect it to work, but it was worth a shot.

After a few hours of hitting my head, I lit on the magic combination. https://drive.google.com/open?id=0B6JAOG...zRMRGF5Zkk

Please note, flag -78 must be CLEAR to direct serial data to the USB port. Additionally, make sure -33 is clear, to transfer over USB and not IR.

I've had issues getting Conn4x to work with this configuration, but I can start the Kermit server with [RShift](hold)&[>] and transfer via Kermit with TeraTerm, so I'm fine with that.

This is only tested on Windows 10. No support. Try at your own risk. Not responsible for anything. But it works for me.

To install, drop that file into a folder by itself. You /may/ need to copy usbser.sys from C:\Windows\System32\drivers\ as well, and place that file next to the .inf above.

Go to the device manager, go to the Drivers tab, and click "Update Driver..."

Select browse manually, let me pick, have disk, and direct it to your folder you made above. It "should" install with that.

I personally am surprised I got it to work. If someone else gets it to work, even with bashing... Well, that's why I'm bothering to post this. Best of luck!

As a sidenote... Driver signatures will have to be disabled to install the bastardized driver. That said, the driver itself is from Microsoft, I'm just supplying the VID and PID of the calculator to tell Windows it's okay to install the usbser.sys driver for this device. What's unfortunate is if HP had the calculator saying it was Class 02 they'd not even had to write drivers at all...

-AL