how much ram does it really have?

[ztimar]

Of course I would try to install exactly the same type of RAM M12L128324a-7T

[ztimar]

Of course I would try to install exactly the same type of RAM M12L128324A-7T

The question is: do I know how much RAM I have - from the software?

[rireed3]

Originally Posted by ztimar

Of course I would try to install exactly the same type of RAM M12L128324A-7T

The question is: do I know how much RAM I have - from the software?

OK, you seem to know the part being used in your machine, and that there is a free pad for another part the same size.

I couldn't get to the images that were posted, so I don't know how much else you know. I think it's unlikely that the manufacturer implemented the control refresh hardware to the second pad, so you must become a printed-circuit-surface-mount-device engineer to figure out the new wiring and add the correct new control/refresh part(s) in addition to the memory part. This may also involve electrical parts like resistors that may be discrete or in packages of their own.

Further, if any of the control parts is some sort of masked circuit array, it get's very bad indeed. These are conglomerations of standard logic and timing circuits that the part manufacturer masks according to the machine manufacturer's spec. You need some pretty sharp oscilloscope work to come up with matching array specs so you can buy an array you can program.

Then you're left with what the firmware does with memory. If the above goes well, it's a good bet your mod will be recognised as more memory by the firmware, but not at all certain this will do you any good. If the machines don't use virtual memory, all this work will not make your machine any faster for any file. To find this out, try reading a 16 MB file of any sort -- you simply won't be able to read a 16 MB file if there is no software 'scrolling' or other virtual memory trick.

If you can read these big 16 MB files, and they are a lot slower than smaller files, more memory by the hard work described above would only double the size file you can read more quickly, not make smaller files of any sort any faster.

Richard

[Godzil]

Ho by the way, the ram size can be hardcoded in the device firmware since it's impossible to dynamicaly detect RAM size with reliability... PC station use EEPROM to store memory card informations, that's how a PC detect new memory...

[rireed3]

Originally Posted by Godzil

Ho by the way, the ram size can be hardcoded in the device firmware since it's impossible to dynamicaly detect RAM size with reliability... PC station use EEPROM to store memory card informations, that's how a PC detect new memory...

The way this was done on eb100/eb600 depends on the manufacturer's intentions at the time the design of each board was final. It may well be that the startup ROM can detect the existence of either one or two devices and assign the size properly.

I think that's more likely than having ROM code that needs another change when the manufacturer decides to put on another memory chip.

Edit: What we really need is an insider at Netronix ;-)

[rireed3]

Originally Posted by ztimar

Of course I would try to install exactly the same type of RAM M12L128324A-7T

The question is: do I know how much RAM I have - from the software?

Sorry, I had seen this answered by Godzil further up.

The SDRAM part you mentioned has 128 Mbits, or 16 MBytes, although the chip organisation is in 32-bit words, each one equivalent to 4 bytes. Already you can see how the overal design isn't necessarily straightforward.

Richard

[ztimar]

Thank you for all the comments, I think you're right...
Maybe I need a faster CPU?