Products > Test Equipment

AN8008 US $19, 9999count, 1uV, 0.01uA, 0.01Ohm, 1pF resolution meter

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texaspyro:

--- Quote from: floobydust on August 05, 2017, 07:40:19 pm ---
Instead I  added it to the mV function:
* EEPROM address 0xAC changed from 0x00 to 0x13 adds °C to mV function
* EEPROM address 0xBC changed from 0x00 to 0x15 adds °F to mV function


--- End quote ---

Can you read/write the EEPROM in circuit?   

I've tried reading it in-circuit (using a SOIC-8 clip... which tend to be rather iffy) with a TL866 but all I get back is all 00 or all FF.  I tried with the meter off and on... same thing.  I think the FF's indicate a bad clip connection.   I once got a connection where a few of the read values were non-zero,  but obviously were wrong.  A re-read gave different values.

floobydust:
I don't think you can work with the EEPROM in-circuit as you get bus contention with the DMM IC. TL866 fighting with the DMM IC probably.

I solder-wicked and then lifted up the two 24C02 EEPROM legs SDA SCL and tack-soldered tiny wires, along with  GND (3 wires total) and ran them to a programmer.
Used Arduino sketch with 3V level-translator (resistors/diode clamp) to read/write the EEPROM. #define DEVADDR 0x50    // I2C device address of 24C02 EEPROM
DMM write-protect WP jumper JP2 must be in to allow EEPROM writes. Using DMM 3V power on to run the EEPROM. DMM will give "Err03" I think if it can't see EEPROM.

This is my EEPROM contents with temp. function added. Yours will differ due to CAL coefficients. Do not overwrite yours.
So read your EEPROM, save that then edit the two bytes to allow temperature.

Attached .HEX file is from Russian forums on kazus.ru;  Has 600V alarm voltage instead of 750V I think, and no temperature enabled.

You can change auto-power off time, backlight timer, LCD contrast, alarm voltages etc.

Many people changing EEPROM contents on DMM's using the same IC like ZT101, ZT102, AN8001, AN8002, HP-890CN, HP-770HC, UT139C etc.



--- Code: ---      0  1   2   3  4   5  6   7   8  9   A   B   C   D  E   F

00: FF FF FF FF FF FF FF FF FF 52 00 FA 00 00 BE 03

10: 10 17 0F 27 52 03 6E 50 64 4B 3C 3C 0A FF 40 FF

20: 3C 98 81 81 64 00 96 00 00 80 8D 80 00 80 FE 69

30: 4E 02 09 9C FB 09 8C 01 0A 18 FC 09 36 FC 09 00

40: 00 01 00 01 00 07 98 00 64 00 64 00 64 00 00 00

50: 00 80 00 80 00 80 00 80 00 80 00 80 00 80 00 80

60: 7B 7E EE 7F 0A 00 99 2A 00 00 00 00 00 00 00 00

70: 8B 82 00 80 AC 82 E0 7C 18 01 00 00 00 00 00 00

80: 00 00 00 00 00 16 00 10 00 0C 00 07 13 01 12 03

90: 00 00 00 00 00 00 00 11 00 0D 00 09 15 02 00 04

A0: 00 00 00 00 00 00 00 00 00 00 00 0A 00 00 00 00

B0: 00 00 00 00 00 00 00 00 00 00 00 0B 00 00 00 00

C0: 0D 00 02 10 0D 00 03 20 20 00 03 20 20 00 03 10

D0: 1F 80 FF 7F 00 80 00 80 41 00 03 05 0D 00 02 20

E0: 00 80 00 80 00 80 00 80 00 80 00 80 00 80 00 80

F0: 0F 80 FF FF FF FF FF FF 5A C7 CC 0F 0F A2 00 00
--- End code ---

Kerry Wong has some info on his site where he was into the EEPROM.

floobydust:

--- Quote from: Gandalf_Sr on August 05, 2017, 08:41:12 pm ---
--- Quote from: floobydust on August 05, 2017, 08:14:55 pm ---ANENG upped the price to USD $32, what is this capitalism lol

--- End quote ---
Which model did they increase the price on? I still see the AN8008 on eBay for $13 $23 from China.

My AN8008 just arrived in the mail, so far I've put batteries in it and checked that it seems to operate as expected.

--- End quote ---

Top # orders USD $32.30 now. But other vendors have original communist pricing.
https://www.aliexpress.com/store/product/ANENG-AN8008-True-RMS-Digital-Multimeter-9999-counts-Square-Wave-Backlight-AC-DC-Voltage-Ammeter-Current/

tronde:

--- Quote from: texaspyro on August 06, 2017, 12:10:48 am ---
--- Quote from: floobydust on August 05, 2017, 07:40:19 pm ---
Instead I  added it to the mV function:
* EEPROM address 0xAC changed from 0x00 to 0x13 adds °C to mV function
* EEPROM address 0xBC changed from 0x00 to 0x15 adds °F to mV function


--- End quote ---

Can you read/write the EEPROM in circuit?   

I've tried reading it in-circuit (using a SOIC-8 clip... which tend to be rather iffy) with a TL866 but all I get back is all 00 or all FF.  I tried with the meter off and on... same thing.  I think the FF's indicate a bad clip connection.   I once got a connection where a few of the read values were non-zero,  but obviously were wrong.  A re-read gave different values.

--- End quote ---

When I read or write to the EEPROM in the DTM0660 based VC921 I clamp down the oscillator with a 1kohm resistor across the xtal. Don't know if it OK to short it with a wire. I use a cheap CH341-based programmer and a clip.

kalel:

--- Quote from: floobydust on August 06, 2017, 01:57:20 am ---
--- Quote from: Gandalf_Sr on August 05, 2017, 08:41:12 pm ---
--- Quote from: floobydust on August 05, 2017, 08:14:55 pm ---ANENG upped the price to USD $32, what is this capitalism lol

--- End quote ---
Which model did they increase the price on? I still see the AN8008 on eBay for $13 $23 from China.

My AN8008 just arrived in the mail, so far I've put batteries in it and checked that it seems to operate as expected.

--- End quote ---

Top # orders USD $32.30 now. But other vendors have original communist pricing.
https://www.aliexpress.com/store/product/ANENG-AN8008-True-RMS-Digital-Multimeter-9999-counts-Square-Wave-Backlight-AC-DC-Voltage-Ammeter-Current/

--- End quote ---

It sure received a lot of attention lately. Price did not rise on eBay (yet) but maybe all vendors might increase it in time? Well, I thought about this meter for a long time and in the end I got a rebranded an860b+ for less than an8008 and personally think it will provide more utility. But then, most people here are using it as their second-third-tenth meter, so being smaller is better.

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