HP48G Hardware Troubleshooting Questions/Tips

[TomC]

Compare the Flipse chematic with the diagram in the HPJournal 6/91 which shows the connector on the calculator - they do NOT agree)

(10-17-2019 04:34 PM)rprosperi Wrote:  

(10-17-2019 04:14 PM)TomC Wrote:  By the way, if memory serves me correctly, the referenced 48 schematic by (by Marcel Flipse)has incorrect wiring of the serial port. I wish we could a hold of an editable copy of that schematic!

The pin-out shown in this schematic is of the 48 DEVICE itself, while the pin-out shown in the Technical Interfacing Guide is of the CABLE, so they appear to be opposite, but are in fact, in-sync with each other.

Unless you mean the circuit itself is incorrect; can't help with that.