Sniffing the Rigol's internal I2C bus

[Carrington]

Some changes in the input stage (resistor and trt) from NON-A to A (in Black HW 2.0 NON-A):



I guess that they have also changed some capacitors. Any volunteers to measure their value?
Note: Resistor without marking code -> unknown value.

[Carrington]

Analog Devices ADR5044A (4.096 V Precision Micropower Shunt Mode Voltage Reference) has a R2W marking on it. (See bottom of page 14):

...

Not sure if any other devices has the same R2W marking on them too or not.

Impossible. Must be a NPN trt. I'm pretty sure that is a BF93A (R2*).

* = p -> made in Hong kong.
* = w -> made in china.


Other possibilities (NPN and SOT23 only):
http://www.ecadata.de/searchnew/index2.html

[Carrington]

Mode 0 and Mode 1?

...

Likely the BMODE pins of the BFIN - toggle between flash/spi boot - where spi is what they use to flash the bootldr - one of my first posts in that thread was regarding bmode pins.
if somebody wants to mess with them with boundary scan u can check the bfin pins logic levels nicely.

Maybe I read it. I no longer remember.
Sorry.

[Wim13]

Also posted in the main Rigol topic, but for the others, i updated my bandwidth chart with the 300 Mhz option.
There is not much enhancement for the non A models. Even worse, it not very stabel the 300 Mhz
option . That is i think why Rigol never sold 300 Mhz versions of the non A.

Some others also measured, and there are differences around 1 dB, which is normal
for devices at the end of there capabilities. These measurements are all made on the same 2072.

So i will stay for DSEZ, the E for CAN and the Z for DS2202 with al options.

Edit: the bandwidth is measured only on hardware version 1.0.1.0.0

[alank2]

Even worse, it not very stabel the 300 Mhz option.

Can you expand on this a bit?  What was not stable?

I looked at my other 2072 which has been untouched until now.  It has 3 keys VSAB, VSAC, and VSAE to load the trial options, so my theory that the SN/model are loaded with keys is false.  The 4 keys for the unit that was dumped here probably includes a can trial too which explains the extra key.

[m-joy]

So i will stay for DSEZ, the E for CAN and the Z for DS2202 with al options.

Huhu. So DSEZ does enable 200Mhz and all options including CAN but no 300Mhz.?

Greets

[staze]

And remind us, is this the 2072 hw 1 or hw 2?

And did you self-cal with each of these bandwidths?

[Wim13]

The entry chip LMH6518, has to the datasheet several options, 200 ,350 or 650 Mhz.

as far i can see for 200 Mhz DS2202, it has already open the 350 mode. I dont
think Rigol has used the 650 Mhz option. But only stretched the gain for 350 Mhz to
get the 300 Mhz bandwidth, which gives on the old models not the correct functionality.

See chart below from the datasheet,

[PA0PBZ]

*bump* Anyone having an idea how to convert a non-A model into an A? I also tried 'samegrading" (using the same latest software update), but again no difference. What I am after is the switchable 50 ohm input, I don't think there is much difference between the A and non-A models apart from that.

Well, I changed the jumper settings on my non-A version 2 hardware to reflect the -A settings (moved one resistor from the upper row to the lower row), but I can't find anything that has changed. The 50 Ohm is still greyed out and the model is still non-A. It has the latest software, and I tried booting with left-F6. Maybe it needs a factory reset, but I'm not sure how to do that.

[elecBlu]

Can you expand on this a bit?  What was not stable?

his frequency response of the 300MHz option is not nearly as flat as it could be, look at his chart. But, as far as i remember, he has HW 1.0.
If that chart looks the same for HW 2.0, you better leave it at 200MHz.

Interesting to see that the A Models are not identical with HW2.0. So we have at least 3 different input stages out there.

[Rigol-Friend]

is the switchable 50 ohm input

Bad idea:
Quick and dirty you can have 50 ohm impedance by activating the relay for the 50 ohm resistor with a mechanical switch. If your hardware is version 2, relay and resistor are build in.

That will be not elegant, but will work, I think.

[m-joy]

I cant understand whats so special about the 50 ohm impedanz. You can easily get a T-connnector with 50ohm Terminator so whats the point.

[Gallymimus]

I cant understand whats so special about the 50 ohm impedanz. You can easily get a T-connnector with 50ohm Terminator so whats the point.

It's a lot more convenient than using an external adapter, why are you trolling?

[Wim13]

I cant understand whats so special about the 50 ohm impedanz. You can easily get a T-connnector with 50ohm Terminator so whats the point.

There is a very big difference, if you terminate directly on the chip entry, or on the BNC connector,
gives a lot of impedance changes.

[Wim13]

Can you expand on this a bit?  What was not stable?

You can see on 1 nsec the DS2000 hw version 1.01.1 has difficulties display the correct waves,
it also differs when you switch two channels on, the signals changes...so not reliable.

DS2000 old version where never designed to work behind 200 Mhz. The hardware had to be modified,
as they did on later models.

[clifford]

I cant understand whats so special about the 50 ohm impedanz. You can easily get a T-connnector with 50ohm Terminator so whats the point.

There is a very big difference, if you terminate directly on the chip entry, or on the BNC connector,
gives a lot of impedance changes.

For signals under 300 MHz the few centimeters of transmission line stub should not be an issue. But it nevertheless feels better to have the termination where it belongs: right at the end of the transmission line.

[Git]

I'm having a few issues with my JTAG probe

Thanks for your efforts on this. Did you manage to do a JTAG verify of dump file against the device?. I'm not very familiar with DS code, but there is a lot of 0xFF empty space in the dump which would make me suspicious if I had dumped it.

[bigmarkslp]

Does anyone know if the USB port unlock trick works with the A series?  I've been trying to decide between an non-A or A series unit, and the A series seems better from a hardware perspective.

[Carrington]

For signals under 300 MHz the few centimeters of transmission line stub should not be an issue. But it nevertheless feels better to have the termination where it belongs: right at the end of the transmission line.

And, what about the rise time?


About R2W smd marking code:

Made in China: http://www.chipdip.ru/search/?searchtext=BFR93A+%28SMD%29+SOT23
Made in Hong Kong: http://www.soltronik.pl/bfr93a-12v-50ma-6ghz-135db-sot23-tranzystor-npn/p-15171.html?osCsid=7d3806245e986140f752be4951f2c818

[alank2]

Does anyone know if the USB port unlock trick works with the A series? 

What trick is this?

[Git]

What trick is this?

There's mention of it here :
http://hackaday.com/2013/07/02/unlocking-a-rigol-scope-once-again/
also there was a Service Mode hack.

Git

[alank2]

There's mention of it here :
http://hackaday.com/2013/07/02/unlocking-a-rigol-scope-once-again/
also there was a Service Mode hack.

Unlocking as in installing a test key?

Is there a service mode hack for the ds2000 besides the menu7-menu6-menu7 one?

[bigmarkslp]

also there was a Service Mode hack.

There is studio25's Atiny85 trick too, right?

[jkw13]

I think I've "bricked" my new DP832 by downgrading it to v1.06 and back to v1.08.
ADC cal doesn't work anymore, and the display meters are wrong.
Is there any way to recover from this do you think? Perhaps I did something wrong?
Does anyone know the ManualCal procedure?   
Thanks!

The problem is not the firmware up / downgrade.
There is a bug in the manual calibration.
Only volts and current ADC are affected.
The DAC's are ok.
Rigol knows the problem.
I'm waiting for a new firmware.
Write a mail to the Rigol support.

Is there more to  it than this I wonder?
Rigol say v1.08 is the latest version.
I find it strange that in addition to the ADC problem
that the options are lost after downgrade/upgrade,
including the trial minutes that I had.
I would like to remove the options and try again,
but ":SYSTem:OPTion:UNINSTall" doesn't work in
Ultra Sigma, nor ":Cal:Start 2012,CH1" either

[clifford]

And, what about the rise time?

I would rather worry about overshoot:



This is for 0 cm, 1 cm, 5 cm and 10 cm stubs, using vacuum (air) as dielectric. So this should correspond to about 0 cm, 0.5 cm, 2.5 cm and 5 cm stubs for real world dielectrics.