Dim OLED Screen replacement for Agilent Keysight U1253A U1253B U1273A U1273AX

[DavidAlfa]

Start reading few post back.

[fbpicsous]

Thanks a lot, we just saved 2x U1253B !
I buy "midas" oled:
https://midasdisplays.com/shop/oled/oled-graphic/mcot128064ey-ym/
Works great.

Unfortunately the capacitive measurement does not work anymore with the new firmware U1253B !???
(Both MM affected)

[DavidAlfa]

Does it work again with unmodified fw?
Maybe the patch area was not empty after all, I could try relocating the code elsewhere.

[gamalot]

I'm having trouble upgrading the firmware version of my U1253B (from 2.26 to 3.04). The screen keeps showing "D...." and the PC keeps repeatedly asking me to cycle the power of the multimeter to continue the upgrade process. I gave up after trying this dozens of times. Any suggestions? 

[DavidAlfa]

Try official update first?

[gamalot]

Try official update first?

It was the official one. 

I actually tried every version I could get my hands on, the official 2.26 and 3.04, as well as the patched 3.04.

[DavidAlfa]

Can't tell. Maybe bad cable driver? Depleted batteries?

[gamalot]

Can't tell. Maybe bad cable driver? Depleted batteries?

I've tried the original U1173B and my DIY CH340 cable, but none of them worked.

Regarding the battery, I tried powering it with a bench power supply.
 
I also used the method you mentioned in post #33, but there was no visible change.

[DavidAlfa]

Can't help, sorry.

[gamalot]

Can't help, sorry.

Thank you very much for your reply. Now the only hope left is whether it is possible to write the firmware directly through the Flash Utility.

[DavidAlfa]

The screen keeps showing "D...." and the PC keeps repeatedly asking me to cycle the power of the multimeter to continue the upgrade process. I gave up after trying this dozens of times. Any suggestions? 

Are you sure the U1173B optical cable is working?
Try disabligng any other COM ports in the Device manager.
Also try changing the assigned port to COM2 or COM3, removing the cable and plugging it back afterwards.
Just to make sure, try with a USB 2.0 socket!

I also used the method you mentioned in post #33, but there was no visible change.

This is only to start the mcu into native bootloader mode.
It's totally unrelated to the Keysight bootloader the updater talks to.

Now the only hope left is whether it is possible to write the firmware directly through the Flash Utility.

Theorically yes, you could. But it's risky!
First, I would try only erasing block 127, then writing a ramdom 1KByte file to it.
If it fails, the bootloader will be still intact and enter update mode automatically.

Code: [Select]

python flash-util.py -e -b 127 -p COM3
python flash-util.py -f "1kb_file" -b 127 -p COM3


If it was able to erase and write that block, then you can try wiping the chip and writing the whole firmware.
You need to first convert the original file into the native binary with tool_U1253B_U1273A (Available here):

Code: [Select]

tool.exe firmware.AG firmware.bin

Then flash it:

Code: [Select]

python flash-util.py -e -p COM3
python flash-util.py -f firmware.bin -p COM3


[gamalot]

Thank you very much for such a detailed reply, I have double checked the cables and as mentioned I have also tried different cables and changed port numbers. I even found an old Thinkpad T410 laptop with only USB 2.0 and installed WIndows 7/8.1/10 operating system, etc., without success. That's why I said my last hope is to use Flash Tools to write the firmware, I'll try it soon and report back.

[gamalot]

Pinout of ports on U1253B.

[gamalot]

My CH340 based U1173B clone.
 

[DavidAlfa]

How does that clone compare to the official cable?
It seems nowhere close to me, looks like the original cable goes inside of the socket while yours is flat.

Pinout of ports on U1253B.

Just trace the same pins:

1. pin   50    P14/RxD6

2. pin   51    P13/TxD6

3. pins   18    EVSS,
            60    AVSS

4. pins   16    REGC,
            19    VDD,
            20    EVDD

5. pin   10    RESET (via 1K resistor)

6. pin   13    FLMD0

[gamalot]

It works just as well as the original, maybe a little better, since the PL2303 converter that Keysight used in their cables is no longer supported by Windows 11.

One thing I thought of before trying to use the flash tool directly was to wire out the reset signal to a button, as I found that my U1253B didn't always have a reliable power-on reset.

[onesystem]

When debugging my U1273AX after flashing wrong firmware onto it I did a reset of the chip by simply shorting two wires for a moment and that worked for me.

[Tarloth]

Thanks to everyone, I was able to change the screen, update with the modified firmware and revive a U1253A without any problems (using the Bluetooth adapter). EVERYTHING WAS PERFECT, THANKS TO THOSE WHO MADE THIS POSSIBLE.

Gracias DavidAlpha por tu esfuerzo!

[Per Hansson]

This is an off-topic reply but I'm hoping it helps save someone else:
I have been meaning to put NiMh batteries in the U1273Ax I showed on the previous page but have not been to IKEA yet.
I thought for sure it can work fine with some Alkalines for just a few weeks.
They where unused and from the same batch, expiry date December 2027
Looks like the second cell from the left in the attached picture shorted.
It smells burnt and is blackened, however all cells show quite nominal voltages from left to right both with a high and low impedance measurement:
1.497v 1.461v 1.485v 1.524v (I did check the batteries voltage before putting them in the meter and then they where all within a few mV).

So I expected something inside the meter had shorted (like a capacitor) but nothing looked burnt.
So I powered up the meter from a bench PSU and it draws a normal load and works fine.
So this is your call to find all Alkalines batteries in your possession and get rid of them, thank me later
In my case the only part that took damage was one of the battery series metal clips, so I got lucky.
I was going to measure something with the meter and it was totally dead: I guess the clip no longer made contact and that stopped the carnage...

[DavidAlfa]

They look cheap, don't put crappy batteries in expensive equipment, use the good stuff like Energizer, Duracell...

[Per Hansson]

They look cheap, don't put crappy batteries in expensive equipment, use the good stuff like Energizer, Duracell...

Thanks but I respectfully disagree: I have Energizer batteries that leaks when unused in the original plastic packaging.
My thinking for putting "cheap brand" (these are marked by a local store chain in Sweden) is that unlike the large names they probably don't spend time eeking out the last bit of battery capacity:
With the hope that there should be more internal spacing for the internal seals, obviously that didn't work in this case but my only advice for everyone in this thread is to not use Alkalines, ever.
The previous owner seem to have had a battery leak in this meter too, one of the battery posts is degraded just like in Daves video #1564.

[Tarloth]

Hi, I use the U1253A today to measure capacitors and the meter it's dead, change the scale up to mF and nothing happens. Any idea? Thanks

[DavidAlfa]

Define "dead".
Or is it only failing to scale to mf?
@onesystem could you test this on yours?

[Tarloth]

Sorry @DavidAlfa!, yes, the capacitor measurement reads nothing, change automatically from nF to uF and then to mF, after few seconds shows the overrange "OL" but never sees the capacitor. Before flash the new firmware I did measured a couple of caps (with inverted screen) and did works ok. I attach an image of the problem.

EDIT:Everything indicates that it will make a normal measurement going through all the scales but as if I never connected the capacitor to the measurement circuit. If I connect the thermocouple (same dial position but using the shift) the measurement is perfect.

[voltsandjolts]

@Tarloth

Is the capacitor in circuit, or out of circuit?

What is the expected capacitor value? Is it within the measurement range of your meter (see specs)?