Dim OLED Screen replacement for Agilent Keysight U1253A U1253B U1273A U1273AX

[DavidAlfa]

Great! 
Did anyone try the latest test from above?

[Fallenrecruit]

Hey Brains trust I have a U1461A Insulation Multimeter that uses a u1273-26501 Display that has got a case of the fade, Does anyone know or can look to see if the firmware mod can be done for this meter

[DavidAlfa]

The cheap oled might work out of the box, give it a try?
The fw size is 256KB, so it must be a different uC. Open it out and show some pictures!

Edit: It's a UPD78F1168A (12:30), uses 78K0R architecture, way different than 78K0 used by the MCUs on u1253/73 (16-bit mcu vs 8-bit).

[DavidAlfa]

I found a way to disassemble the firmware on 78Kxx devices!

Download "CubeSuite+ for CA,CX" from Renesas (Requires registration) or Drive, then follow the attached picture.

Loading binaries doesn't work (Throws illegal file error), but Hex does, can be converted with HxD (Export... 32-bit Intel Hex).
The file from U1461A firmware update (U1461A_V302.AG) needs the same byte/nibble swapping as U1273, so use the same tool, then load the output into HxD and export as Hex.

Attached the files for anyone wanting to play with them.

I located the oled initialization at address 0x130

Code: [Select]

       303132      MOVW            AX,#3231H
       33          XCHW            AX,BC
       343536      MOVW            DE,#3635H
       37          XCHW            AX,HL
       38394142    MOV             4139H[C],#42H
       43          CMPW            AX,BC
       444546      CMPW            AX,#4645H
       47          CMPW            AX,HL
       48494a      MOV             4A49H[BC],A
       4b4c        CMP             A,0FFE4CH
       4d          CMP             A,[HL]
       4e4f        CMP             A,[HL+4FH]
       5051        MOV             X,#51H
       5253        MOV             C,#53H
       5455        MOV             E,#55H
       5657        MOV             L,#57H
       58595a      MOVW            5A59H[B],AX
       2d          SUB             A,[HL]
       5e5f        AND             A,[HL+5FH]
       482020      MOV             2020H[BC],A
       713306      CLR1            P6.3H
       712306      CLR1            P6.2H
       f528ff      CLRB            !PM8
       f53800      CLRB            !PU8
       f408        CLRB            P8
       714206      SET1            P6.4H
       715206      SET1            P6.5H
       716206      SET1            P6.6H
       306400      MOVW            AX,#64H
       fc9e0900    CALL            !!99EH
       717206      SET1            P6.7H
       717306      CLR1            P6.7H
       306400      MOVW            AX,#64H
       fc9e0900    CALL            !!99EH
       717206      SET1            P6.7H
       30ae00      MOVW            AX,#0AEH
       fc9f0200    CALL            !!29FH
       30ad00      MOVW            AX,#0ADH
       fc9f0200    CALL            !!29FH
       308a00      MOVW            AX,#8AH
       fc9f0200    CALL            !!29FH
       30a800      MOVW            AX,#0A8H
       fc9f0200    CALL            !!29FH
       303f00      MOVW            AX,#3FH
       fc9f0200    CALL            !!29FH
       30d300      MOVW            AX,#0D3H
       fc9f0200    CALL            !!29FH
       f6          CLRW            AX
       fc9f0200    CALL            !!29FH
       304000      MOVW            AX,#40H
       fc9f0200    CALL            !!29FH
       30a000      MOVW            AX,#0A0H     <<<--- Segment remap cmd
       fc9f0200    CALL            !!29FH
       30c000      MOVW            AX,#0C0H         <<<--- Scan direction cmd
       fc9f0200    CALL            !!29FH
       30a600      MOVW            AX,#0A6H
       fc9f0200    CALL            !!29FH
       30a400      MOVW            AX,#0A4H
       fc9f0200    CALL            !!29FH
       308100      MOVW            AX,#81H
       fc9f0200    CALL            !!29FH
       30aa00      MOVW            AX,#0AAH
       fc9f0200    CALL            !!29FH
       cf258eaa    MOV             !8E25H,#0AAH
       30d500      MOVW            AX,#0D5H
       fc9f0200    CALL            !!29FH
       304000      MOVW            AX,#40H
       fc9f0200    CALL            !!29FH
       30d800      MOVW            AX,#0D8H
       fc9f0200    CALL            !!29FH
       f6          CLRW            AX
       fc9f0200    CALL            !!29FH
       30d900      MOVW            AX,#0D9H
       fc9f0200    CALL            !!29FH
       308400      MOVW            AX,#84H
       fc9f0200    CALL            !!29FH
       f6          CLRW            AX
       90          DEC             X
       fcb40200    CALL            !!2B4H
       00          NOP             
       712206      SET1            P6.2H
       306400      MOVW            AX,#64H
       fc9e0900    CALL            !!99EH
       30af00      MOVW            AX,#0AFH
       ec9f0200    BR              !!29FH


[Tarloth]

Excellent Work David! THANKS

[Fallenrecruit]

Well the new SSD1309 screen arrived and got it swapped out, It looks great but ill have to say the firmware modification is a bit beyond me would it be too much to ask for some more help?

[DavidAlfa]

First of all we need to find some programming software to make sure we can unbrick it.

Maybe this:
https://github.com/danielnilsson9/78k0r-pgm

[serco]

Hello everyone,

I’m new to programming microcontrollers and could really use your guidance to ensure I’m doing everything correctly. I’ve recently soldered a screen to my multimeter, and I’m seeing the expected mirrored image. Before I proceed with programming, I want to double-check my plan since this is my first time attempting this.

Here’s what I’ve planned so far:
1. Install the PL23XX_Prolific driver.
2. Connect a USB 2.0 to TTL UART adapter to Multimetr
3. Pull FLMD0 to 3.3V to activate programming mode.
4. Run the utility U1253B_Firmware_Update_Software_V304. Do I need any additional software to program the multimeter, or is it sufficient to just launch this utility?
The multimeter will remain powered off throughout the process.

Does this setup look correct?
Thank you in advance for your help!

[Per Hansson]

You can skip step 3: it is only necessary if you brick the meter and it will not accept a firmware update.
When the meter works it is just a "normal" firmware update with the only caveat that you have to use the update tools listed since the newer ones check that the firmware is original before flashing...
So it can also be flashed via IR if you have the adapter for it...

[serco]

Thanks for your reply.
Do I really need to install PL23XX_Prolific driver for my USB-to-UART converter?

[Per Hansson]

No, you only need a driver that can communicate with the serial converter chip in your unit, I used one by Sparkfun if you look back at my posts here and it worked fine.

[serco]

Thanks for your code and description