smithj@jacobs.CS.ORST.EDU (Jeremy Smith) (03/14/90)
>From: pete%slack.uucp@cs.utah.edu (Pete Ashdown) > > Rick Sterling was kind enough to post the pin-outs for the 48's serial > connector recently. However, he did not specify what was needed to actually > make the connector. Does anyone know the TRaSh-Shack equivalent to plug into > that hole? Also, which pin is #1? & > From: wscott@EN.ECN.PURDUE.EDU (Wayne H Scott) > > Hello everyone, > > I have a 48sx and am planning on hooking it up to my computer but I just can't > see spending $35 on a cable I could build myself. > > Is the serial port anything close to a standard connector? What have other > people used to jerry rig a connector? +---------------------------+ HP 48sx Description RS232 | +------+ | Pin equivalent | | 1234 | | 1 Chassis Ground 1 | \____/ | 2 Transmit data 2 | | 3 Receive data 3 +---------------------------+ 4 Signal Ground 7 Looking directly into port. The above is info received from Rick Sterling. I made a connector with it and, together with a null modem cable (crossing lines two and three), it works like a charm. I have uploaded and downloaded programs from my PC to the Charlie. I enclose the following warning/disclaimer so that it is freely distributable: [WARNING: The following Rube Goldberg/Heath Robinson/Micky Mouse/String&sellotape/chewing gum&paperclip procedure is not recommended, may void HP's warranty, might damage your HP 48sx, and might even work. Follow entirely at your own risk. Any resultant damage is no fault of the source of this procedure.] _____ \ (hp) | 48sx | ___ |connector null modem / PC | | RS-232 4 |---------7 7-----------7 | db 9 3 |---------3 3-----, ----3 | or 2 |---------2 2---- `-----2 | db 25 1 |---------1 1-----------1 | plug | `--- _____/ For the connection to the 48's pins: on a regular db 25 connector there are sockets on the female, and pins on the male. The sockets are readily available in packets of 10 in either solder or crimp types (even from radio schack!). I think you could find connectors that fit on the 48's pins better, but might have to hunt more. > From: a309@mindlink.UUCP (George Lin) > > Also, for the HP serial plug, I scavanged the connector from a broken floppy > drive. And, if I remember correctly, pin #1 is closer to the "F" key. > (pin #4 is closer to the "A" key) The sockets have two long 'lips' forming a tube. I squeezed these together slightly with a pair of pliers. / \ / | | | \ end on view \ / \ | of socket / before after I crimped (in my case, rather than soldered) the four sockets to four wires, and insulated each connector. (I just happened to have some very thin 'ptfe' tubing perfect for the job, but anything to insulate them from each other will do). I then placed them on a piece of tape exactly 2mm apart (which is the distance of the pins from each other, as close as I could eyeball with a ruler), and then wrapped the tape around. The other ends of the wires were connected to the regular db25 serial connector. Bingo! ________________________ // / / / \ || \ | \ | \ | \ | | \ | \ | \ | \ || \__/______/______/______// tape-----^ | | | | +------+------+------+ 2mm 2mm 2mm Yer luvin' Uncle Bert |-)