Hi All,
I recently picked up this fine virus and started tinkering with HP-41's and their related hardware. I started with the HP-41CV I purchased many years ago and fixed the flex-cable and started 3D printing various parts.
Then I was able to acquire an HP-IL interface, HP-IL printer, and PIL box. I 3D printed the connector based on the STL files I found and started getting hooked at getting everything connected.
My collection was extended with a full-nut HP-41C and this all worked fine as well I got the card reader, was able to revise it and am now looking at ways to fix the printer rollers in two printers I acquired as well.
Now my problem and the subject of this topic. Yesterday I got a delivery or a full-nut HP-41CX to complete my collection of calculators. I was able to hook it up with the rest of the components and was a happy camper. Until today. All of a sudden I only get "TRANSMISSION ERROR" when trying to use the HP-IL interface. So I tried the other machines and they didn't seem to have an issue.
So to narrow down my troubleshooting and before I start to take everything apart. What are the most common causes of this error?
My initial thinking it must be the flex-connector, as the other two calculators have this replaced.
Any suggestions and things to look for are highly appreciated.
By the way, I also got the NoV-64 module, so I can also have a look at ROMs that may be helpful to diagnose this.
Regards.
Bas