I didn't know about that, thanks. Undocumented feature? Doesn't seem to make a difference in my case though. Hard to do, too, because if I hold it a fraction of a second too long it just goes into the menu. Using 1.11k r355 by the way.
As per Chinese ESR meter I'd like to buy a model that could be upgraded with project improvements. No external power, accuracy and shortcuts would be no problem as I could fix them by myself. But crystal and programming header would be nice (or at least a socket 328)...
This one look nice (crystal, socket, large display, upgradable?) :
http://www.aliexpress.com/item/12864-LCD-GM328-transistor-tester-ESR-meter-Cymometer-square-wave-generator-Free-shipping/2052241237.html
I Have this one http://www.aliexpress.com/item/frss-shipping-5pcs-latest-Version-Mega328-Transistor-Tester-Diode-Triode-Capacitance-ESR-Meter/1778135807.html same software execpt for display part. Would appriciate information on how to to upgrade firmware I Have the old software for a 2 line alphanumeric display. But my hardware is with a graphical LCD display (newer version!): here it is - feel free to collect it : https://app.box.com/s/rj03grtur3xonxi7mzud
nothing obvious at mikrocontroller.net site. i dont speak german and like many diy hobbyists not good with code suppositories.
can anyone help me please?
i got a Chinese transistor tester and tried to update it using the k-firmware now no screen wont display anything. i got the transistor tester 2014-07 by fish8840
thanks
thanks for the input. I installed a HD4480 LCD and it works ok now.
now this display is 16x2
can i use a 20x4?
Here is my early version of the new Tester with some modifications.
The 10-pin ISP header is soldered, but one side of the frame must be cut out
to match the room left for the header.
The original potentiometer has been replaced to a exemplar with higher resistance
(10k) to save power.
Two blocking capacitors of 100nF each are additionally mounted near the ATmega.
The D1 zener diode is replaced by a precision voltage reference like LM4040AIZ2.5 .
If you don't have a precision voltage reference, you should remove the zener diode at least.
I had also replaced the original 78L05 regulator by my preferred MCP1702-5002 regulator,
because this regulator can also save quiescent current.
Regards, Karl-Heinz
I bought the graphical LCD version from EBay (fish...)
The period shouldn't be part of the link:
111329306664
Is it also getting warm? Whenever a regulator does this to me, it's usually because it doesn't like the capacitors on its input or output. The great thing about 78L05 is that it's stable under the same conditions that would make other ones oscillate like crazy. HTH
I replaced the zener with the 2.5V reference and everything works OK. When I replaced the 78L05 with the recommended LDO regulator, the board still works, but now reports that the 9V battery is low, at 7V. Yes, I did take into account the different pinout between parts.
Things didn't go so well this time. I do get text on the screen, but it looks mirrored and upside down. It also looks too large and ghosted. Obviously, there are some differences between the standard firmware and/or hardware and what this Chinese guy made. I can't go back to the original firmware, because AVRDUDE says the file is corrupt.
The period shouldn't be part of the link:
111329306664
I replaced the zener with the 2.5V reference and everything works OK. When I replaced the 78L05 with the recommended LDO regulator, the board still works, but now reports that the 9V battery is low, at 7V. Yes, I did take into account the different pinout between parts.
Have you checked the battery voltage and Vcc (+5V) with a DMM?
So, I decided to go for broke and see about updating the graphic version that I just got. It also needed a header (out the back of the board for the correct pinout), but this one did not appear to be locked. I made a backup of the firmware, then flashed the ST7565 1.11K firmware.
Things didn't go so well this time. I do get text on the screen, but it looks mirrored and upside down. It also looks too large and ghosted. Obviously, there are some differences between the standard firmware and/or hardware and what this Chinese guy made. I can't go back to the original firmware, because AVRDUDE says the file is corrupt.