[champagnecharly]

Or.. we get the best we can and upgrade. Parts are available. Well.. it seems that way.
The only thing that I dont think can be changed is the USB as the main board is modified for a smaller chip.

Answers: (i am reciting not first hand experience)
1) AMB2300 is required for later firmware.
2) By search for module spec sheet and verifying. E.g.search for K6R4016C1D and see the UI10 is one of many specs and pin configurations..
3) look at the spec sheets I posted and also the images that Dtech reposted (originally from fantomel) How there is the circular shape in each corner and how one is a full circle.. not sure what is meant by mirror mark as if it was true mirror it would be full circle also. In can you see the markings reffered to. Also do look at the PDF specs of the OKI as you see different chips/format have diff markings.

Wouldnt it be nice if somebody had an original 5054a we could look at...

[DTech]

A) AMB2300 is a must for all firmwares after 2.2.2 version up
b)UI = industrial quallity
UT = normal ones
-10 = 10ns
C1D = 5V
so, long story short: memory must be 4Mbit SRAM, 256KX16, 5V, 10ns, TSOP 44 pin
c)Mirror mark= circle into circle in lower part of chip and between them is shiny like a mirror
You can try and see when OKI has EOL (10 years ago) and also AU5780 chip that is EOL
Both of them are used for J1850 PWM & VPW protocols.
Hardware check of interface is in line mode, meaning one after another so , no AU you get error and oki is not checked.
700.2115 Fault on vehicle bus access J1850-PWM
700.2116 Fault on vehicle bus access J1850-VPW
Meaning these 2 errors, one for oki one for AU. Solve 1 get the other after

Little hint: Use good old VAS-PC to check your interface.

[apoelistas]

Which is better UT or UI?
1. What is UF memory?? Is this acceptable?
2. 3.3V ?
Do these have a description / code?

Thanks

Who sells a perfect version???

[Marcos]

Which is better UT or UI?
1. What is UF memory?? Is this acceptable?
2. 3.3V ?
Do these have a description / code?

Thanks

Who sells a perfect version???

http://www.samsung.com/global/business/s..._rev20.pdf

[apoelistas]

So getting the 3.3V samsung 55 memory chip is ok???I believe it s a slower chip because it uses less energy thus runs cooler and response time is 55ns compared to 10ns. Would this produce a problem in vas5054a when firmware upgrading a control unit???? For a 10 mins flash run time with the 10ns chip what would be the flash time with the 55ns chip???

Theoretically I am not worried of having a 3.3V chip unless this is known to cause a functionality/instability problem. I would try of course to get the better one e.g. 55ns rather than 70ns.

[DTech]

3.3V memory operates at higher voltage, so for how long is the question? If you look in datasheets you will see the upper limit of x model. This means will overheat and will brick
This is why you do not change voltage of chips.
Time: 55ns; 70ns; original 10ns(low power consumption if you read datasheet). Not a problem if head is slower of you might loose some info on the way because of slow ram

[apoelistas]

A slower ram of 3.3v in spec means that it will operate at 5v due to vas5054a design??? Then this will not be long lasting and unstable.

Question
Is there a vas5054a with uf55 that runs memory with 3.3v as designed, or is this not possible??

Can one upload photos of original vas5054a board??

[Marcos]

A slower ram of 3.3v in spec means that it will operate at 5v due to vas5054a design??? Then this will not be long lasting and unstable.

Question
Is there a vas5054a with uf55 that runs memory with 3.3v as designed, or is this not possible??

Can one upload photos of original vas5054a board??

The original head has RAM working at 5V.
Speed and voltage in this case doesn't have anything in common.
In other words : Clones !!!MUST!!! use the same voltage RAM as genuine ones.

[apoelistas]

I will pass, uf55 or uf70 are not acceptable. Thanks for explaining.

Checking for a VAS5054a with following prerequisites, I get zero results.
1. AMB2300
2. Memory with the code 10 (as discussed).
3. with original OKi chip

[obd2cartool]

3.3V memory operates at higher voltage, so for how long is the question? If you look in datasheets you will see the upper limit of x model. This means will overheat and will brick
This is why you do not change voltage of chips.
Time: 55ns; 70ns; original 10ns(low power consumption if you read datasheet). Not a problem if head is slower of you might loose some info on the way because of slow ram

From the overall analysis, CPU running speed is very important, RAM speed too fast, will also cause energy waste ,right?