anyone need POGO cable for HP 20b/30b, HP 15C LE?

[hojeongko]

I found a way to get a POGO cable that works for the HP 20b/30b, HP 12c+ (2008-2005), HP-12c 30th, and HP 15c LE.

Here
6pin pogo connector
erase and reset button
Anyone can perform flashing using .

Necessary items
1. POGO cable(the calculator store), POST 2015 HP 12c, HP 15c CE
2. USB A extend cord.
3. PL2303HX USB to TTL RS232.
4. Soldering tools.

When you remove the case of the PL2303HX, you will find the board inside.
Use a soldering iron to separate the cable.

Cut the USB A extend cord.
Only use the USB A (female) part.
Peel off the wire and reattach it to the board prepared above.
When connecting lines, you must be aware of TX and RX.

When first disconnecting a wire from the board, check the color of the connecting wire carefully.
Afterwards, solder the prepared USB A cable again, but this time, solder it in a different color from the existing one. That is, connect the Tx of the board and the Rx of USB, and connect the Rx of the board to the Tx of USB A. Vcc is not used. GND connects to GND in the same way.

If you've done this, your work is done.
If you connect the newly made product with the pogo cable shown in item 1, it becomes a flashing cable for voyager using ARM versions prior to 2015.

When the gender is separated, it becomes a flashing cable for arm-using voyagers from 2015 or later to suit existing uses.

[ijabbott]

Make sure the USB-to-TTL serial converter is set for 3.3V TTL and not 5V TTL. Sometimes there is a slide switch or a jumper to change the signal voltage between 3.3V and 5V.

• Pin 1 of the USB socket (VCC +5V, usually a red wire) not connected.
• Pin 2 of the USB socket (D- signal, usually a green wire) goes to TXD on the USB-to-TTL-3.3V serial converter.
• Pin 3 of the USB socket (D+ signal, usually a white wire) goes to RXD on the USB-to-TTL-3.3V serial converter.
• Pin 4 of the USB socket (GND signal, usually a black wire) goes to GND on the USB-to-TTL-3.3V serial converter,
  

Some people recommend the use of a 1KΩ resistor on the TXD signal, at least for the HP 20b/30b because they are expecting 3V signal levels, not 3,3V, and the resistor mitigates for the slight over-voltage.

You don't have to use PL2303 modules. FT232R or CH341A modules should do as well, as long as they are TTL 3.3V (sometimes written TTL 3V3).

[hojeongko]

ijabbott
Your point is correct.
Anything is possible as long as USB to TTL3V3.
However, the mention of the PL2303 module is because I made a cable with it and did flashing.

The key to this article is to get a 6pin POGO connect.
And the key is not to make any modifications to the flashing cable you purchased.
In other words, if you create a conversion module, you can flash both before 2015 and post 2015.

(06-15-2024 07:11 PM)ijabbott Wrote:  Make sure the USB-to-TTL serial converter is set for 3.3V TTL and not 5V TTL. Sometimes there is a slide switch or a jumper to change the signal voltage between 3.3V and 5V.

• Pin 1 of the USB socket (VCC +5V, usually a red wire) not connected.
• Pin 2 of the USB socket (D- signal, usually a green wire) goes to TXD on the USB-to-TTL-3.3V serial converter.
• Pin 3 of the USB socket (D+ signal, usually a white wire) goes to RXD on the USB-to-TTL-3.3V serial converter.
• Pin 4 of the USB socket (GND signal, usually a black wire) goes to GND on the USB-to-TTL-3.3V serial converter,
  

Some people recommend the use of a 1KΩ resistor on the TXD signal, at least for the HP 20b/30b because they are expecting 3V signal levels, not 3,3V, and the resistor mitigates for the slight over-voltage.

You don't have to use PL2303 modules. FT232R or CH341A modules should do as well, as long as they are TTL 3.3V (sometimes written TTL 3V3).

[fossy]

Hello,

the discription of the converter was not 100% clear for me, but I could realize it. For all other I will post my additional description with drawings an photos.

Another question for me was "how to programm the LE". The SamBa.exe mentioned in the descripton for the new programming cable does not work to program the LE. BTW. the LE need another firmware. The firmware of the CE does not work for the LE.

POGO connector of the LE:
   

Converter for the new programming cable to program the LE
   

Drawing of cable and converter with pinning

   

Pinning of USB-A
https://allpinouts.org/pinouts/connector...erial-bus/

Firmware for the LE
<https://www.hpmuseum.org/forum/thread-18491.html>

find the post of "Katie Wasserman" and the links

• Version 4/11/11 2011-04-11
• Version 4/15/11 2011-04-15 this is the firmware the LE was sold with
• Version 8/19/09 2009-08-19
  

The oldest version (2009-08-19) does not have the PSE-Bug - but it has the Overflow-Bug and as mentioned later in the post eventually most other bugs.

The Overflow-Bug is also annoying. At overflow or when Flag 9 is set (SF 9) the display blink only once and is then off, but the calculator is still on. The blinking (and not seen blinking) can be stopped by [<-] or [ON] [ON].

Windows Program to program the LE

You will need the MySamBa.exe . It will run on a WinXP (and I think also on Win7, Win10, Win11).

Link to MySamBa.zip <https://sourceforge.net/projects/wp34s/files/FlashTool/>


Programming

If you connect the new cable with the converter and press ERASE and RESET you will erase (empty) the firmware. If you cannot program another (or the same) firmware your LE will be bricked.

Before you can programm the LE you must get it in the programming mode - sadly this will erase the actual firmware.

To erase the actual firmware and get the LE into the programming mode do

• press and hold ERASE
• press and release RESET
• release ERASE
• press and release ON
• press and release RESET
• press and release ON
  

After this start MySamBa.exe select the USB-serial converter (COM whatever on your computer), the firmware and press "Send" and wait (ca. 20 seconds).