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Flashing 34s via USB--Prolific ruled out entirely?
Message #1 Posted by Les Wright on 10 Nov 2011, 8:36 p.m.

Hi folks,

I have the 30b, the cable from Gene, and a USB-Serial adapter that I have had for years and claims to have the Prolific chipset. I have updated the drivers accordingly. I am trying to flash under XP with MySamBA.

On my XP setup, Device Manager tells me the USB-Serial adapter is mapped to COM3. I pick that out in MySamBA, find the calc.bin file, and press Send File. The thing hangs for a few minutes and gives a little dialog box with an Unable to Connect error.

I am assuming I have the dreaded Prolific issue and really need to get the other type of adapter (FTDA or something like that?)

I guess my question is whether anyone has got this to work with a Prolific adapter. If there is any way to make this cable work, I would love to know. If not, I would like some direction as to the kind of USB-Serial adapter that people who have flashed over USB under XP have used successfully.

Many thanks,

Les

      
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #2 Posted by Eric Rechlin on 10 Nov 2011, 10:53 p.m.,
in response to message #1 by Les Wright

I have used this cable with success.

Eric

            
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #3 Posted by Les Wright on 10 Nov 2011, 11:31 p.m.,
in response to message #2 by Eric Rechlin

Thank you, Eric.

It is a little more expensive than I was hoping to pay, but if it works I can scarcely complain. To be frank, that Prolific cable was cheap and I don't think ever got it to work with any serial device. Good money after bad...

The cable will also get use when there is a firmware to the HP15C LE and I need to reflash that calc.

Many thanks for that--I ordered it post haste.

Les

                  
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #4 Posted by Marcus von Cube, Germany on 11 Nov 2011, 2:11 a.m.,
in response to message #3 by Les Wright

I've opened the little case on the cable, stripped the board off all electronics and soldered an FTDI 3.3V TTL cable directly to it instead of the cable end with the D connector. This has the added benefit that the cable no longer draws any current from the calculator to feed the level shifter. There is no level shifting involved at all.

BTW, without a voltage regulator you can't use the USB supply lines to feed the calculator because they are 5V, not 3V. I've added a plug so I can connect an external power supply to feed my development calculator.

                  
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #5 Posted by Bart (UK) on 11 Nov 2011, 5:32 a.m.,
in response to message #3 by Les Wright

I can vouch for the FTDI converters. I have a standalone module and it works for other applications too. It is a bit more costly, but worth it. Searching through previous posts on the subject also will confirm many 20b/30b flashing probems were solved when an FTDI based converter was used.

regards
Bart

      
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #6 Posted by Egan Ford on 11 Nov 2011, 7:01 a.m.,
in response to message #1 by Les Wright

Quote:
On my XP setup, Device Manager tells me the USB-Serial adapter is mapped to COM3. I pick that out in MySamBA, find the calc.bin file, and press Send File. The thing hangs for a few minutes and gives a little dialog box with an Unable to Connect error.
Can you still turn the calculator on? If so, then it was not ready to be flashed.
            
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #7 Posted by Les Wright on 11 Nov 2011, 3:28 p.m.,
in response to message #6 by Egan Ford

Yup. With the calc connected, it turns on and off just fine. The reset button on the cable does exactly that. A cautious press of the Erase button does nothing.

What should I be seeing on the calc if I have achieve a proper connection?

Les

                  
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #8 Posted by Marcus von Cube, Germany on 11 Nov 2011, 3:58 p.m.,
in response to message #7 by Les Wright

Press and hold erase, then press ON to make the processor run and it will properly erase.

                        
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #9 Posted by Les Wright on 12 Nov 2011, 6:15 p.m.,
in response to message #8 by Marcus von Cube, Germany

Thanks Marcus, erasing obviously worked because I now have a calc that won't turn on :)

Still getting the "unable to connect" error.

Will try again with the proper adapter I ordered from Eric. If that doesn't work I guess I have bigger problems!

Cheers,

Les

                              
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #10 Posted by Marcus von Cube, Germany on 13 Nov 2011, 3:27 a.m.,
in response to message #9 by Les Wright

Remove the batteries while you wait!

                                    
Re: Flashing 34s via USB--Prolific ruled out entirely?
Message #11 Posted by Les Wright on 14 Nov 2011, 7:55 a.m.,
in response to message #10 by Marcus von Cube, Germany

Thanks Marcus. I bought a whole bunch of CR2032 batteries in bulk a while ago. I swapped out the once fresh pair from the 30b into my 17bii+, and sure enough the low batt indicator flashed momentarily when I turned the latter on.

I understand the flashing procedure puts a high drain on the cells if it doesn't go well. I am glad I have quite a few spares around just in case. I am surmising from your warning that an erased 30b puts a higher draw on the cells.

Les


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