Interface details for Deskjet 932C

[Wizard353]

I have a $58K medical diagnostic instrument that is married to a a HP 932C color printer.  I can no longer buy ink for this printer.  The instrument has closed software, and only a 25 pin IBM PC DB25 Centronics parallel printer output connection. 

I have tried to capture the raw PCL output stream from the instrument to the printer with a vintage Microbuffer device and a current RetroPrinter interface unit.  When connected to either capture device, the instrument times out and gives a "printer not ready" error.

The diagnostic instrument does output properly to the 932C color printer and to a HP 1100 B&W printer, but I would like to get the color output back.  I have learned that the 932C has an IEEE 1284B Bidirectional interface but I have been unable to obtain any more detailed interface information from HP.  Does anyone have detailed interface info on these printers that would let me determine the problem with the interface?  Otherwise, I'll have to make a 265 pin breakout adapter and hang a logic analyzer on the output to figure out why it's not working.  Thanks in advance!  Dave

[zoey7886]

@Wizard353, Welcome to the HP Support Community!  

Thanks for reaching out about your query regarding capturing raw PCL! 

We're thrilled to have the opportunity to assist you and provide a solution.  

For capturing raw PCL output from your medical diagnostic instrument connected to an HP DeskJet 932C printer, understanding the limitations and requirements of your specific setup is key.

The HP DeskJet 932C uses an IEEE 1284B bidirectional parallel interface, which allows for communication between devices and is more complex than standard unidirectional parallel interfaces. Unfortunately, detailed information regarding the exact interface specifications or protocols used by the HP DeskJet 932C is generally proprietary and not publicly documented in detail.

Here are some general guidelines and suggestions that might help you troubleshoot or work within the limitations of your setup:

Bidirectional Communication: Ensure that the capture devices you are using support IEEE 1284B bidirectional communication. Devices like the Microbuffer or RetroPrinter should be capable of handling this, but make sure they are configured correctly.

Timeout Settings: Check if there are settings that allow you to adjust timeout periods on the capture devices or on the printer. Lengthening the timeout might prevent the "printer not ready" error.

Compatibility Mode: If possible, try configuring the diagnostic instrument to use different printer compatibility modes. Some older devices output in multiple modes that can be selected.  

Hope this helps! 

Take care, and have an amazing day!  

Did we resolve the issue? If yes, Please consider marking this post as "Accepted Solution" and click "Yes" to give us a helpful vote - your feedback keeps us going!  

Regards,

[Wizard353]

The diagnostic device is a closed system.  I think it is running Windows CE, but there is no way to change any of the configurations.  It has no USB connections and only a 25 pin IBM PC parallel Centronics printer output.  There is no way to access the operating system, of even se4e a file directory. 

When i output to the RetroPrinter device, I get a 90 page result of garbled text.  I have yet to decode the error dumps from the GhostPCL subprogram in the RetroPrinter.

Are there any color PCL 5 capable  HP Printers with a Centronics interface for which color ink is still available?  That would be the easiest approach to my problem.

[zoey7886]

@Wizard353, welcome back! 🌟

I can imagine how frustrating it must feel when a critical medical instrument is tied to aging printer tech and ink becomes a treasure hunt. The Deskjet 932C actually speaks PCL3GUI, not full PCL5, which is why your RetroPrinter captures look like pages of scrambled noise. It also relies on bidirectional IEEE 1284 handshakes, so if the capture device doesn’t “talk back,” the instrument throws a printer not ready error.

If you’re looking for a color replacement that still plays nice with Centronics and has ink available, the Deskjet 990C/995C series is usually the closest sibling — same language, same feel, just easier to find cartridges (HP 45/78). Some older Color LaserJets (4550/4600) support true PCL5c over parallel, but they’re bulky.

Might be worth exploring the 990C route first — it’s often the smoothest swap without rewriting what the instrument expects to hear.

Hope this helps! 

Take care, and have an amazing day!  

Did we resolve the issue? If yes, Please consider marking this post as "Accepted Solution" and click "Yes" to give us a helpful vote - your feedback keeps us going!  

Regards,