$20 LCR ESR Transistor checker project

[flywheelz]

@madires,
The weird issue is still there but only if I restart with the switch.  If restarting with SPI it doesn't show up.

The video was a great idea. It's not a bug, it' a feature. That "noise" is the uninitialized display RAM. Normally you would first clear the display/RAM and then turn the display output on. I'm doing it the other way around to give the user an immediate visual feedback when powering on. The video shows nicely how slow the initial LCD_Clear() is. For a ILI9341 (240 x 320) it takes about 2 or 3 seconds at 8MHz. Those LCD controllers don't got a fast built-in clear function and require you to send "black" (or whatever background color you prefer) for each pixel. Since the ST7735 isn't extremely slow, you could try and move the power-on section in LCD_Init() to the end. Maybe just LCD_Cmd(CMD_DISPLAY_ON), and removing MilliSleep(120).

I followed your advice and we are noise free!   

https://youtu.be/VzCNo60r0-E

[hapless]

TBH, for some reason it looks more attractive to me with the noise than without. 

That SPI transfer looks painfully slow. Is this with an 8MHz crystal? Must be because it can't use the MCU's USART...

[Macbeth]

Hmm... I wonder if instead of changing the colour for the whole field you can do a trick that we used back in the day on the BBC Micro in its monochrome MODE 0 or MODE 1 and was first used successfully on the original BBC Micro Elite ("Hi Res mono" for the game display, but "Lo Res colour" for the scanner/dashboard at the bottom of the screen). That alone was a marvel to me.

Basically it comes down to changing the mono colour pallette at a scan line interval. Of course there are no scan lines as such now, but you could easily separate say 3 obvious colour fields in the display and still get away with 1 bit rendering by applying the change at a couple of serial offsets?

[madires]

Nice idea, but I haven't seen any color LCD modules supporting a monochrome mode. Usually they have different color interface modes, like 12, 16 and 18 bits.

[Pukker]

@flywheelz and others,

[/quote]

I followed your advice and we are noise free!   

[/quote]

Can you post that latest M version please?
Like to have a look at the M version, K version works OK BTW.

Thanks

[madires]

Please download 1.24m at https://github.com/svn2github/transistortester/tree/master/Software/Markus, and if you got the same clone (DIY Kit "AY-AT") as flywheelz, apply the changes he posted one page back.

[flywheelz]

@flywheelz
Can you post that latest M version please?
Like to have a look at the M version, K version works OK BTW.

Thanks

Update:  I've removed the attachment because some testers got white screen.

Go HERE and get 1.25m with the fix compiled by jm_araujo.

Here is a compiled "Component Tester trendy v1.24m" firmware for mega328 color kit AY-AT with ST7735 lcd running @ 8MHz.  I have included the clean boot and what I called a magic lights versions.  Changed src files included. 

Features:

• Enabled HW_Encoder
• Enabled HW_REF25
• Enabled HW_Zener
• Enabled HW_FREQ_COUNTER
• Disabled SW_IR_RECEIVER
• Disabled SW_OPTO_COUPLER
• Changed Menu label Zener to Voltage

To get a Voltage reading, you have to press/hold switch.

[trex13]

Hi everybody,

Does anyone know why I can't download flash from working Chinese LCR-T4 tester using Arduino together with avrdude as ISP programmer ?

I have this version :



I programmed my Arduino to act as ISP programmer, connected everything, run Avrdude from command prompt :

Code: [Select]

avrdude -c avrisp -p m328p -P COM3 -b 19200 -U flash:r:"MtesterFlash.bin":r -U eeprom:r:"MtesterEeprom.bin":r -U lfuse:r:"lfuse":r -U hfuse:r:"hfuse":r -U efuse:r:"efuse":r
At first it seemd OK, but later on I saw that flash file is empty while eeprom is OK but only 1KB in size :

Code: [Select]

C:\tester\noovi>avrdude -c avrisp -p m328p -P COM3 -b 19200 -U flash:r:"MtesterFlash.bin":r -U eeprom:r:"MtesterEeprom.bin":r -U lfuse:r:"lfuse":r -U hfuse:r:"hfuse":r -U efuse:r:"efuse":r

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.03s

avrdude: Device signature = 0x1e950f (probably m328p)
avrdude: reading flash memory:

Reading | ################################################## | 100% 20.13s

avrdude: Flash is empty, resulting file has no contents.
avrdude: writing output file "Mtester207Flash.bin"
avrdude: reading eeprom memory:

Reading | ################################################## | 100% 3.33s

avrdude: writing output file "Mtester207Eeprom.bin"
avrdude: reading lfuse memory:

Reading | ################################################## | 100% 0.01s

avrdude: writing output file "lfuse"
avrdude: reading hfuse memory:

Reading | ################################################## | 100% 0.01s

avrdude: writing output file "hfuse"
avrdude: reading efuse memory:

Reading | ################################################## | 100% 0.01s

avrdude: writing output file "efuse"

avrdude: safemode: Fuses OK (E:FF, H:D7, L:FF)

avrdude done.  Thank you.
Having in mind that fuses are set like this : "E:FF, H:D7, L:FF" - Avrdude should be able to read flash

Does anyone have any idea?

[madires]

Reading the ATmega is disabled. But you can reset the fuses and program a new firmware. And the "original brand" is laughable. They've taken the orginal open source firmware and changed the display output. And the circuit is also open source.

[techie]

Latest T3 / T4 schematics (Rev. 1d) courtesy of Roland Elmiger.

Note about flashing alternate software:
The latest pre-compiled version of Karl-Heinz software provided on "http://www.mikrocontroller.net/svnbrowser/transistortester/Software/trunk/mega328_T3_T4_st7565/" , v1.12k build 683, does not work (blank LCD screen) with the unmodified version of this tester.
This is due to a change in the Makefile made in March 2016:
line "#CFLAGS += -DPULLUP_DISABLE" was un-commented in build 661, making the LCD SPI interface open-drain with no pull-ups.
Hence, display data is not received by the LCD.

To restore proper operation on unmodified testers, make sure these options exist in the Makefile, and re-compile:
#CFLAGS += -DPULLUP_DISABLE
CFLAGS += -DLCD_SPI_OPEN_COL
CFLAGS += -DSTRIP_GRID_BOARD #(if it's a strip grid board - you made need to try both settings)

The LCD in these units requires +3V +/-10% VDD, while the Atmega runs on +5V VDD.  The PCB design includes two 1N4148 diodes in series from +5V VDD to the LCD VDD to attempt to drop the 5V down to something more reasonable for the LCD: ~3.6V, assuming 0.7V drop per diode. In reality, the LCD voltage is higher because of the small current drawn by the LCD, hence smaller diode drops.

Karl-Heinz suggests removing these two diodes and replacing them with a proper +3.3V LDO regulator, such as the MCP1703-3302.
He also recommends installing two additional pull-up resistors (10K - 30K) on the SCL and RST lines of the SPI bus between the Atmega and LCD.
They should pull-up to the +3.3V LCD supply.

If these hardware modifications are made, the compile Makefile options would be the same as the 683 build:
CFLAGS += -DPULLUP_DISABLE
CFLAGS += -DLCD_SPI_OPEN_COL
CFLAGS += -DSTRIP_GRID_BOARD #(if it's a strip grid board - you made need to try both settings)

Please see attached picture of suggested hardware mods from Karl-Heinz.

For owners of this tester which is offered on ebay under the designation as "LCR-T3" or "LCR-T4 Transistor Tester" I offer a way to update firmware. Devices have identical G-LCD (ST7565), but slightly different PCB. Update works on both versions of this tester. However, attention should be given to the fact that the ISP connector from the parts is mirrored. For this purpose I have pieced together a simple detachable adapter enabling the MCU to program without arranging the auxiliary ISP connector (see attached pictures). Many thanks to Roland Elmiger (hb9gaa) from the official discussion forum for providing the schematic diagram.

[Pukker]

Here is a compiled "Component Tester trendy v1.24m" firmware for mega328 color kit AY-AT with ST7735 lcd running @ 8MHz.  I have included the clean boot and what I called a magic lights versions.  Changed src files included. 

Features:

• Enabled HW_Encoder
• Enabled HW_REF25
• Enabled HW_Zener
• Enabled HW_FREQ_COUNTER
• Disabled SW_IR_RECEIVER
• Disabled SW_OPTO_COUPLER
• Changed Menu label Zener to Voltage

To get a Voltage reading, you have to press/hold switch.

Thanks flywheelz,

Sorry to say but doesn't work for me, screen lights up, power stays on, but nothing on the display.
I have exact the tester as shown on your picture. Works OK with the K-version, svn 684
Maybe any tips, what can be wrong.

Thanks anyway for your effort.

[madires]

Have you compiled the firmware yourself or used the firmware provided by flywheelz? In the first case you need to change some pin and display settings (see flywheelz' post one page back).

[Pukker]

Have you compiled the firmware yourself or used the firmware provided by flywheelz? In the first case you need to change some pin and display settings (see flywheelz' post one page back).

I have used the firmware provided by flywheelz.
I don't have much knowledge about compiling and so on.
When I have time I hope to study that to.

Thanks for reply.

[stj]

there are several T4 variants around, some use "strip grid" and some dont.
and it pisses me off that they are all called T4

[stj]

@Pukker
if you have SVN 684 then it probably came from me.
if so, it probably has the makefile in the zip - upload it for Flywheelz & others to use.

[Rudolf_h]

hi !

im new and i need help :-)

http://www.ebay.at/itm/2016-EZM328-transistor-tester-ESR-frequency-meter-square-wave-genera-KITS-/172230778097?hash=item2819c11cf1:g:K8EAAOSwnNBXU~VH

i am from austria and my english is not the best

i habe payd this but the chip is empty ;(

how can a download the hex ans eep file ?

thx Rudolf 

[flywheelz]

Thanks flywheelz,

Sorry to say but doesn't work for me, screen lights up, power stays on, but nothing on the display.
I have exact the tester as shown on your picture. Works OK with the K-version, svn 684
Maybe any tips, what can be wrong.

Thanks anyway for your effort.

I am surprised it did not work.  Maybe the kits are a little different.  If it powers on I am guessing the firmware is running but not talking to display correctly or on wrong data ports.  Try leave the tester powered on and if it turns off in about 30 seconds then firmware is running.

I will re test the previous files but in mean time you can try the attached firmware with default data ports 321.

Also check out this post, maybe it will get you compiling. *Collection of Helpful information *

edit:
I am new to fuses but the ones I used are : -U lfuse:w:0xF7:m -U hfuse:w:0xD9:m -U efuse:w:0x04:m

[stj]

hi !

im new and i need help :-)

http://www.ebay.at/itm/2016-EZM328-transistor-tester-ESR-frequency-meter-square-wave-genera-KITS-/172230778097?hash=item2819c11cf1:g:K8EAAOSwnNBXU~VH

i am from austria and my english is not the best

i habe payd this but the chip is empty ;(

how can a download the hex ans eep file ?

thx Rudolf

code:

[Pukker]

@Pukker
if you have SVN 684 then it probably came from me.
if so, it probably has the makefile in the zip - upload it for Flywheelz & others to use.

STJ

Yes that files came from you.
Works perfect.
Makefiles hereby. BTW, I didn't use them.

Thanks for willing to help.

[flywheelz]

@Pukker,

I tried both the clean boot and the magic lights versions I posted on my unit and they work. 

Can you post pictures of your tester? 

Is it 8MHz or 16MHz? 

What fuses are you using?

@stj,
I also tried your svn684 v2 8MHz it worked fine.  I don't know really know why the 1.24m I compiled works on my AY-AT but not Pukker's.

[Rudolf_h]

hi

Thanks for the software, problem view video

https://youtu.be/sUbec_VTAhI

[stj]

i dont watch video's
(they hate my browser)

[flywheelz]

i dont watch video's
(they hate my browser)

What the heck you still use Lynx from 1992?

From video, tester at menu, goes into "Transistor" by itself, shows a read of a 10.3ohm resistor then says "Timeout!" then turns off.

[vinceroger]

hi

Thanks for the software, problem view video

https://youtu.be/sUbec_VTAhI

I have two of these testers im using the firmware you have downloaded and it works fine what are the fuse settings your using? what programmer are you using for the re programming,

[Pukker]

@Pukker,

I tried both the clean boot and the magic lights versions I posted on my unit and they work. 

Can you post pictures of your tester? 

Is it 8MHz or 16MHz? 

What fuses are you using?

@stj,
I also tried your svn684 v2 8MHz it worked fine.  I don't know really know why the 1.24m I compiled works on my AY-AT but not Pukker's.

I've have exact the same unit as the picture in post 2506 from flywheelz
8Mhz crystal
Fuse used:
lfuse:w:0xF7
hfuse:w:0xD9
efuse:w:0x04

Thanks for reply.