Sinclair ZX80 / ZX81 / Z88 Forums

I don't know how evolution works, but if you're talking about firmware updates then hmm, I think that ZXpand does that already - the firmware for the ZXpand can flash itself, but as commander is just a normal P file then all you need to do is copy it to your SD card. Are you concerned because the source files are there in the archive too? They're only present in case anyone wants to add a feature - the P file is all most people will actually need.

Have I understood correctly?

C

sirmorris wrote:I don't know how evolution works, but if you're talking about firmware updates then hmm, I think that ZXpand does that already

Hmm. I see. Does it mean there is something more to flash, beside of the Firmware?
And this particular thing cannot be "re-flashed" from the level of ZX81?
(Sorry, You realize I know crap about hardware ).

The only thing that ZXpand can update is the firmware for the controller chip on the interface. This is done by placing a file on the SD card. The interface also contains an EPROM which holds the 'operating system' program - this can't be updated unless you have access to EPROM programmer hardware. The chip needs to be removed from the board, erased, then programmed with new code.

The string printed at machine reset 'ZXPAND X.Y' indicates which version of the controller firmware you have. Doing the SD card flsh will update this. The EPROM also has a version number, but this can only be displayed from BASIC:

PRINT PEEK 7679 / 10

I hope that helps, Yerz!

What SirMorris is saying, is that ZXpand has two main parts (not including the 32k RAM):
1) a small independent micro-controller (a small computer on a chip) which has it's own FLASH "ROM" memory to control it, all in the same physical chip, it is this chip which interfaces between the Z80 CPU and the SD card,
and
2) a EPROM that has the code in it to add the commands and functions executed by the ZX81's Z80 CPU so that a user can control ZXpand from BASIC

Mark

Ah, thx guys.
So I have no access to EPROM programmer. So that's what I meant.
OK, just asking anyway.

Dammit, I should have listened more closely in 'explaining things better' class..!

No dude, this is my crap English appearing in its full majesty.

Anyway, returning to the main topic - on Eva it is still dangerous. I can re-flash both - baseconf and ROM but if it goes dead while re-flashing...... Hehe.

They made accessible some small "emergency prog" and seems like it solves the possible "unpredictable" problems, that's another thing.

Anyway - I don't suppose it would be possible to make the existing ZXpand fully "flashable" (haha) from the ZX81 level.
Maybe in some next version.

Actually it is.. Both Siggi and I have fully flashable boards. You need a new memory decoder chip though.
If you need a new EPROM I can sort you out, but I thought you already had an up-to-date (ish) ROM.


C

Yes yes, I have. And I don't complain at all.
So who knows - maybe in Germany, if we'd be going next year, heheh.
OK, thx!

I have been using COMMANDER 1.8 with ZXPAND 2.3 and it locks up when trying to create a DIR (shift+K). I type the name hit ENTER and "freeze frame".

Problem with SDHC 16GB card?