Alternative WP34S flashing using Arduino

[zelez]

Hi,

anetzer say:
"Just wanted to thank you for the very readable and practical instructions. I got my hands on an Arduino and managed to flash a handful of 20B's in practically no time."

I have same experience.
I've just flash two hp20b calculators
using Arduino Duemilanove.
Works like a charm.
Thank you for sharing idea and excelent manuals.

Bye
zelez

[mendesp]

Thank you for these instructions. Since I can't flash my calculator, I was wondering if this is because my Arduino nano clone is equiped with a CH340G chip instead of the genuine FTDI ?

Anyone having success with a CH340G ?

Regards,

Patrick

[subaffo]

Hi,

I was preparing my Arduino (One) to flash a 20b but then I stopped:

the Tx,Rx levels are at 5V, not at 3.3V.

I haven't seen any resistor on those lines in the schematics.
Most of the Arduino boards are at 5V levels.

Did I miss something in the (fine) documentation of this flashing method?

Thanks to all

Fabio

[emece67]

I've been asking myself why such "unexpected" method to flash an wp34s gets so many positive comments. Specially existing some other, cheaper, devices better suited to this task than an Arduino board. A USB to RS232 converter working at 3V3, as in the image, can be get from TAS for less than $2.



I suspect that the culprit is that this method is accompanied by full instructions in a single, all encompassing, PDF document. Perhaps people (like me) using other "more standard" ways to flash their wp34s can write such documentation for their systems.

Thanks adamkov for your nice approach.

[subaffo]

The point is, emece67, that Arduino can easily be already available on the desk or in the drawer of a lot of people: it can be quite convenient.

I agree with you that purposely get an Arduino for this would be quite fool, given the alternatives we have.

And... yes, a well documented method is surely a big advantage and help to the many that would like to transform their 20-30b. Not everyone is an electronic wizard and besides the mythical HP cable and the, unfortunately too, now unavailable Harald's boards, the "average wannabe" user's only chance is to wander in the forum trying to imagine how to connect wires, erase etc....

So, ok, I'll get one of the simple USB-TTL interfaces and will try to put notes and photos to share.

(by the way: someone there who used Arduino at 5V TTL levels is around? Ok: the RX from Arduino can easily be dropped to 3V with two resistors 4k7 -10k to ground. But TX at Arduino side still is 5V while HP sends 3V: just put a 1k?!?)

Fabio

[pdicamillo]

Clearly not a cost-effective solution for everyone, but if you already have an Arduino, or would like one for other uses, it's great. I have an Arduino Nano from arduino.cc, and I believe it has a genuine FTDI chip. Following these directions, my flashes (using MySamBa) have always worked the first time (unless I made a mistake.) That comes after a great deal of frustration with an inexpensive serial adapter from China with a Prolific chip. I didn't add any resistors to reduce the 5V, and had no issues, although that's probably is a good idea.

[CakeyLies]

Hello I'm newer to the wp 34s spaces but I just got what I thought was all the pieces I needed to flash a HP 30b with the wp 34s rom. But I'm suck on mysymb step because both windows program don't seem to see the calculator. I tried with both an arduino and a ftdi cable from Amazon. Any help would be greatly appreciated!

Below is a picture of one of my tries with the ftdi cable.
Red = power +/-
White = RX
Black = TX

Second Image is arduino
Red = Ground
White = RX
Black = TX


       

[slabco]

(12-15-2014 06:09 PM)mendesp Wrote:  Thank you for these instructions. Since I can't flash my calculator, I was wondering if this is because my Arduino nano clone is equiped with a CH340G chip instead of the genuine FTDI ?

Anyone having success with a CH340G ?

Regards,

Patrick

failed too with ch340 series.
successed with the genuine FTDI at the moment I deciderd to give up.

[pangushk]

(05-17-2023 12:46 PM)slabco Wrote:  

(12-15-2014 06:09 PM)mendesp Wrote:  Thank you for these instructions. Since I can't flash my calculator, I was wondering if this is because my Arduino nano clone is equiped with a CH340G chip instead of the genuine FTDI ?

Anyone having success with a CH340G ?

Regards,

Patrick

failed too with ch340 series.
successed with the genuine FTDI at the moment I deciderd to give up.

I cannot find the cable nor any module with FTDI in my hand. Making the custom cable is definitely not my taste, although I have all the pogo pins already!

I successfully flashed with Arduino nano clone (with ATMEGA168 MCU not 328, which does not matter since the flashing procedure would disable it anyway) with CH340C on win11, but
1. has to remove the RX/TX LED on arduino nano clone to make the loopback test works! check this out:
https://forum.arduino.cc/t/arduino-faili...e/473276/8
2. run MySamba with Administrator, or else the program did not see the Serial Port!

Great thanks to all you guys for the great work!!!! I finally convert a HP20B to WP34S !!

[spiff72]

I ended up building a programmer from an Adafruit Metro Mini and a piece of a network cable. I used pogo pins and a 3D-printed connector.

It works fine, but it will probably live in a drawer for a long time before I flash another 30b. It was more of a "because I can" project than a "I need this" project...

https://imgur.com/gallery/VcIulpo

[FreeBlues]

(09-03-2023 10:33 PM)pangushk Wrote:  

(05-17-2023 12:46 PM)slabco Wrote:  failed too with ch340 series.
successed with the genuine FTDI at the moment I deciderd to give up.

I cannot find the cable nor any module with FTDI in my hand. Making the custom cable is definitely not my taste, although I have all the pogo pins already!

I successfully flashed with Arduino nano clone (with ATMEGA168 MCU not 328, which does not matter since the flashing procedure would disable it anyway) with CH340C on win11, but
1. has to remove the RX/TX LED on arduino nano clone to make the loopback test works! check this out:
https://forum.arduino.cc/t/arduino-faili...e/473276/8
2. run MySamba with Administrator, or else the program did not see the Serial Port!

Great thanks to all you guys for the great work!!!! I finally convert a HP20B to WP34S !!

Thanks a lot for your post!
It took me an entire afternoon to try out my Arduino Nano with Ch340C. Although I had a faint suspicion that the problem might lie with the Ch340C, I wasn't certain. After reading your article, I finally confirmed the root cause of the issue. However, removing the RX/TX LED was a bit tricky for me, so I'll have to order an Arduino Nano that uses the FTDI chip. Thank you again!

[FreeBlues]

After using the simulator for two weeks, and experiencing a failure with an Arduino Nano based on the CH430C chip the day before yesterday, I finally managed to successfully flash the firmware on an Arduino Nano based on the FT232RL chip today. I am very grateful to the developers of the firmware and the sharers on the forum; you have created a rather classic calculator!