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Author Topic: Internal memory expansion (Read 198642 times)

Offline Saint

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Re: Internal memory expansion
« Reply #105 on: 2013.October.24. 22:46:49 »
Quote from: Zozosoft
Send the components and I will assemble it!
I could send you kit form if you wish! It's a simple modification -- just requires the 1MB GAL, one trace to be cut, a wire to be run from a pad underneath the board to the SRAM CE and a capacitor between GND and VCC on the top SRAM. I've attached a picture of my 1MB expansion.

I'll let you know when all the bits arrive and when I'm ready to ship! :ds_icon_cheesygrin:

Offline Saint

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Re: Internal memory expansion
« Reply #106 on: 2013.October.24. 22:49:07 »
Quote from: fatbob_gb
My newly installed memory expansion (and EXOS 2.4beta) is working perfectly:ds_icon_cheesygrin:

Sadly another Enterprise membrane gave up the ghost though, luckily I had a spare one handy, better get another one ordered.

Thanks James & Zozosoft also for the updated EXOS.
Great stuff! Glad to hear another is working... :smt041

Taking the Enterprise apart is always a bit of a risk with the keyboard membrane -- do you not have enough length left to cut the end off? I've done that far too many times now... :roll:

Offline fatbob_gb

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Re: Internal memory expansion
« Reply #107 on: 2013.October.25. 00:10:18 »
Quote from: Saint
Great stuff! Glad to hear another is working... :smt041

Taking the Enterprise apart is always a bit of a risk with the keyboard membrane -- do you not have enough length left to cut the end off? I've done that far too many times now... :roll:
Last time I opened it I had to cut the ends off and only just managed to get it back together so I ordered a spare membrane just in case.  When I opened it up tonight what was left of the membrane was so brittle that there was very little that I could do with it. Hopefully the new one will last me for a few years yet, I will still order a spare though.

Offline lgb

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Re: Internal memory expansion
« Reply #108 on: 2013.October.25. 09:00:54 »
Quote from: Saint
Zozo: I've tried the 1MB expansion, and have a working prototype, but it takes me too long to solder on the piggyback chip. It's quite awkward as my hands are not very steady, and the result is quite messy. So I'm afraid I will only be offering the 512KB expansion for the moment. :(
Can it be the option to have all GALs (even the "512K only" versions) programmed for 1M (just one output is simply not used with the 512K version), and buyer can ask for +1 SRAM IC, but its his responsibility to solder the extra SRAM chip piggy-back on the other one and the extra wire from the GAL to the CE line of the new the SRAM IC?

Offline Zozosoft

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Re: Internal memory expansion
« Reply #109 on: 2013.October.25. 13:22:45 »
For the piggy back the best way solder the chips before place to the PCB.

Offline Saint

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Re: Internal memory expansion
« Reply #110 on: 2013.October.25. 19:53:50 »
I've had another go at doing the 1MB board and this time did a nice job if it, and did it quite quickly, so I'll build up and test all the 1MB boards here after all! :)

Using some liquid flux on the chip legs really helped get the solder flowing nicely.

Offline Zozosoft

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Re: Internal memory expansion
« Reply #111 on: 2013.October.27. 22:17:56 »
Currently: 8x1M, 4x512K, another one waiting for answer.

Do you want some money prepaid? (For buying components.)
« Last Edit: 2013.October.27. 23:17:36 by Zozosoft »

Offline Saint

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Re: Internal memory expansion
« Reply #112 on: 2013.October.28. 09:44:32 »
Quote from: Zozosoft
Currently: 8x1M, 4x512K, another one waiting for answer.

Do you want some money prepaid? (For buying components.)
Thanks for offer, I think I'll be OK! I placed quite a large order for SRAM last week, which should cover most of the units, so I'm just waiting on the PCB's and GAL's now to build up the remaining units.

Thanks!

Offline geo1977

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Re: Internal memory expansion
« Reply #113 on: 2013.November.04. 09:22:48 »
Today im very happy my precious Enterprise have 589kb memmory and working without problem :ds_icon_cheesygrin:
THANKS !!!!!!!! JAMES!!!!!!!

Offline Saint

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Re: Internal memory expansion
« Reply #114 on: 2013.November.04. 10:08:21 »
Quote from: geo1977
Today im very happy my precious Enterprise have 589kb memmory and working without problem :ds_icon_cheesygrin:
THANKS !!!!!!!! JAMES!!!!!!!
Great stuff! :mrgreen:

Offline Zozosoft

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Re: Internal memory expansion
« Reply #115 on: 2013.November.05. 07:19:07 »
Currently for Hungary: 8x1M, 5x512K

Offline Saint

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Re: Internal memory expansion
« Reply #116 on: 2013.November.05. 10:17:08 »
Quote from: Zozosoft
Currently for Hungary: 8x1M, 5x512K
Thanks for the update, I have 1x512K and 3x1MB built up ready and the next batch of boards should arrive soon -- they were shipped on the 28/10. I'll get those built up when the boards arrive, then it's just a matter of when the GAL's arrive!!

Offline Zozosoft

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Re: Internal memory expansion
« Reply #117 on: 2013.November.23. 16:55:54 »
Is there any news? :oops:
« Last Edit: 2013.November.23. 17:09:13 by szipucsu »

Offline Saint

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Re: Internal memory expansion
« Reply #118 on: 2013.November.23. 18:34:03 »
Still waiting for pcb's and GAL's... :(

Offline Saint

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Re: Internal memory expansion
« Reply #119 on: 2013.December.05. 11:46:33 »
PCB's have arrived!! I'll start building them up tonight. Still waiting for the GAL's, but at least I can make up the rest of the boards now. Putting the GALs in is a really quick job. :ds_icon_cheesygrin: