Connecting HP 49g to PC.

[matalog]

I have an FTDI 232 board with a DB9 male connector wired to RX, TX and GND. Then I put the RX to pin 2, TX to pin 3 and GND to pin 5 of the DB9 that comes out of the 49g's original serial cable. 49g waiting to connect via XSERV()

I am not having any luck getting this to connect to Conn4x.

I have previously connected the 50g via USB cable and used the FTDI serial adapter to communicate with various serial devices, I have just tested that with a MIDI keyboard and a MIDI breakout board and it works fine.

I was mainly testing with 9600 baud, but it has not connected yet.

Are other (DTR or CTS for example) ports used in the 49g serial cable?

Should I be able to connect the calculator this way?

[Tracer21]

Try swapping RX and TX lines. RX on the Calculator goes to TX on the 232 Adapter and vice-versa. Ground goes to ground.

Check section 3.1 here: http://www.geocities.ws/hpcables/cable49g.htm

49G can at most use 9600 Baud, so that should be fine. Don't need any other serial lines like RTS / CTS.

Does your 49G have XModem Server installed? Mine didn't until I upgraded the ROM.

[matalog]

(01-15-2022 02:39 AM)Tracer21 Wrote:  Try swapping RX and TX lines. RX on the Calculator goes to TX on the 232 Adapter and vice-versa. Ground goes to ground.

Check section 3.1 here: http://www.geocities.ws/hpcables/cable49g.htm

49G can at most use 9600 Baud, so that should be fine. Don't need any other serial lines like RTS / CTS.

Does your 49G have XModem Server installed? Mine didn't until I upgraded the ROM.

I don't know if it does, I just bought it second hand. Is there a way to tell?

Say it doesn't? How might I update the ROM? Hopefully there is a way using my cable hack?

[matalog]

I typed VERSION in the 49g and it said what I thought was 1.1 so then I got out my old Compaq Armada with both Windows XP and 98 on it (serial and parallel port :-)), copied over the 1.18 ROM and HP COMM 30r4 with USB stick on XP then rebooted to 98, installed HP COMM which allowed me to install the latest supported ROM, then I rechecked version on 49g and realised that it wasn't displaying enough text and the version could have been anything above or including 1.10 when I got it, as I needed to VIEW the text to get the full version number.

Knowing that the ROM version I have should support Xmodem I have since switched Rx and Tx around on pins 2 and 3, and left the GND on pin 5. I have had no success yet. I was able to copy the files I wanted to with that old laptop anyway, but not being a quitter, if anyone has any other suggestions for getting this to work on a modern PC, please offer them.

p.s. the serial cable I am connecting the calc to laptop worked fine with the laptop downloading and installing for 10 minutes, and is the same cable that I use the tested and working FTDI 232 on Modern PC, so I assume all cables are fine.
p.p.s. I cannot get the old laptop to perform a successful BACKUP of the 49g on the HP Graphing Calculator Connectivity Kit 3.0r4.

[Tracer21]

If you were able to update the ROM, you should be able to use Conn4X on modern Windows (works on Win 11 for me). Can ignore the note on swapping the RX / TX lines.

On the calc, Right Shift + Right will launch XModem Server, then you can choose the COM port @ 9600 Baud. Click Connect Icon and should see the file structure on the Calc.