464 and ram extension ....

[gerald]

How do I get FutureOs to run on 464, the ROM version are in slot 10 to 13 and 464 only initialize 7 and below ?

[TFM]

How do I get FutureOs to run on 464, the ROM version are in slot 10 to 13 and 464 only initialize 7 and below ?

Uups, can you try to install the ROManager ROM (the version with the Booster), it should init all 32 ROMs.
Else, let me know, I will make a ROMs:2-5 Version.

[gerald]

Uups, can you try to install the ROManager ROM (the version with the Booster), it should init all 32 ROMs.
Else, let me know, I will make a ROMs:2-5 Version.

Looks like the the ROManager ROM does not work on 464. It just crash after being initialized. Behaviour can be checked in WinAPE with 464rom and basic 1.0.
If you really have time to spend, you can make 2-5 rom version, but I do not expect better behaviour of FutureOS on my extension than on DKtronics one.

[arnoldemu]

Code Select Expand

[quote author=gerald link=topic=7246.msg51960#msg51960 date=1350589439]
   with ROM disabled :
r/w in 0x4000-0x7FFF goes to base bank 0xC000-0xFFFF
r/w in 0xC000-0xFFFF goes to extension bank 0xC000-0xFFFF

  with ROM enabled :
w in 0x4000-0x7FFF goes to base bank 0xC000-0xFFFF
w in 0xC000-0xFFFF goes to extension bank 0xC000-0xFFFF
r  in  0x4000-0x7FFF  and 0xC000-0xFFFF return upper rom content

[/quote]
So close except for the read of 0x0c000-0x0ffff. I will test again but I am sure this is ram here, rom only readable in 0x4000-0x7ffff.
btw good job with the fix for 464.

@arnodemu
If you have time,  can you check the 4 lines after the "memory Expansion test" message of my test when run with a dktronic extension on 464 ?
You should get :

I may have time this weekend to do that.

[TFM]

Looks like the the ROManager ROM does not work on 464. It just crash after being initialized. Behaviour can be checked in WinAPE with 464rom and basic 1.0.
If you really have time to spend, you can make 2-5 rom version, but I do not expect better behaviour of FutureOS on my extension than on DKtronics one.

Oh, there is one thing I forget. If you install it into ROMs 10,11,12,13 and an additional copy of ROM A in ROM 0 then it autostarts. But don't waste too much of you time. It would have been just an easy test if C3 works or not.

[MaV]

I have some pics from a recently acquired and yet untested dk'tronics 256k memory. The pcb is labeled "6128 - 256k ver.2" from 1986.

The upload failed despite the size of each of the three pictures being below 400kb. A second upload failed because the forum software tells me there's pictures with the same name already on the server??!?!

Anyway, are they even needed, and if so how shall I upload them?

[Bryce]

Rename them, convert them to png and try again

Bryce.

[Gryzor]

Or resave, or zip, or...

Unfortunately, a known issue with current platform...

[MaV]

I did try again with Pngs but the result was the same. Next try: a zipped file.


Ha, that works! It's three pictures: front, back, and another one of the transistor. The last one looks like a kludge on the board. It's placed very close to the connector and crammed in a position that just doesn't look like a clean design.

[arnoldemu]

I did try again with Pngs but the result was the same. Next try: a zipped file.


Ha, that works! It's three pictures: front, back, and another one of the transistor. The last one looks like a kludge on the board. It's placed very close to the connector and crammed in a position that just doesn't look like a clean design.

please test with my program, I am interested to know what happens with config c3 with this expansion.

[MaV]

please test with my program, I am interested to know what happens with config c3 with this expansion.

That's on my schedule this weekend. I have to get the DDI-Floppy going first (hopefully just the belt), then I'll be able to copy the program and test it.

[TFM]

Well, the PCB tells that it is for 6128, right? So there C3 should work. But is it inteded to be used at the 464/664 too?

[gerald]

@MaV : thanks for the pictures

It's interresting to see that there is still a transistor on a 6128 version. Its position would suggest it drives the MREQn signal, but the way it is mounted on the board does not allow to be sure (tracks cant be seen). MREQn forcing would for sure avoid the timing issue I had on the 6128+ with my own extension.

The A15 forcing transistor seem to have it place reserved too.

[MaV]

I'll try to trace the transistor lines to their next neighbours.

AFAIK, the 256k dk'tronics for the 6128 was also compatible with the 464 and 664. I read that somewhere.

[arnoldemu]

Well, the PCB tells that it is for 6128, right? So there C3 should work. But is it inteded to be used at the 464/664 too?

The reason I ask about c3, is that it has an external PAL within the expansion.
So, perhaps it has the same functionality as the PAL in the 64k dk'tronics and so the c3 configuration does not have 100% functionality with this ram.
But this is something that can be answered with more tests.
of course, the on-board pal within the 6128 will function correctly when the internal ram is selected.

[MaV]

So, the transistor does indeed connect to MREQ. Unfortunately I cannot determine the type of transistor since the flat side of the package is pointing down to the PCB; I've tried  to move it a bit but the connector is in the way.

More precisely:
The base goes to the 12th pin from the right on the lower row of the connector (MREQ; back picture of PCB).
The collector goes to the 12th pin from the right on the upper row of the connector (VCC; back picture of PCB).
The emitter goes to pin 8 of the 74LS11N chip (third chip from the left; front picture of PCB).

If I researched this correctly there are two pin layouts for the 74LS11, one layout tells me that pin 8 is the output of a triple and gate, the other layout says pin 8 is one of the inputs of a triple and gate. It must be the latter pin layout as the former would not make sense.

* MaV confused

[Bryce]

Pin 8 of a 74LS11 is definitely the output of a three input ANDF gate. Where did you find an alternative pinout??

Also. If you don't know what type of transistor it is, how do you know which pins are E, C and B ?? As it's being used as a simple switch rather than to amplify, the value won't matter that much anyway, as long as it the correct type NPN or PNP you can use any general purpose transistor such as a 2N3904 (if it's NPN).

Bryce. 

[MaV]

Pin 8 of a 74LS11 is definitely the output of a three input ANDF gate. Where did you find an alternative pinout??

http://www.alldatasheet.com/datasheet-pdf/pdf/125563/ETC1/74LS11.html

Also. If you don't know what type of transistor it is, how do you know which pins are E, C and B ?? As it's being used as a simple switch rather than to amplify, the value won't matter that much anyway, as long as it the correct type NPN or PNP you can use any general purpose transistor such as a 2N3904 (if it's NPN).

I'm assuming that the pictures like on this page is the standard layout: What is a Transistor - Electronics

And yes, the type should not matter.

[Bryce]

The second pinout (B) is for the flatpack version, the standard DIP 74LS11 is pinout A - Pin 8 = output from 3way AND gate.

The pinout for the transistor you've shown is quite common, but not a standard. There are transistors with alternative pinouts, where for example the collector is in the centre. The transistor used in the CPC+ to switch the tape motor on/off (KTC1815) has an ECB Pinout, ie: Collector in the middle.

Bryce.

[MaV]

The pinout for the transistor you've shown is quite common, but not a standard. There are transistors with alternative pinouts, where for example the collector is in the centre.

Hm, but then the knowing the transistor type would matter after all. But I can't risk breaking its legs by leveraging the transistor. :/

[Bryce]

If you know what the pins are connected to, then it's easy to work out what each pin is. Lets call them 1,2 and 3 for now. What is each pin connected to?

Bryce.

[MaV]

Simply substitute 1, 2, and 3 for the E/B/C of the most common transistor pin layout.

That'll be:
1 to pin 8 of the 74LS11
2 to connector MREQ
3 to connector VCC

If you'd put the transistor in from of you with the flat side on the table and the pins pointing to you: 1, 2, and 3 are counted from left to right.

[Bryce]

Ok, strange, It must be a PNP transistor with BCE pinout (probably something Japanese, 2SBxxxx) .

1 = Base
2 = Collector
3 = Emitter

But that would mean that it switches /MREQ high when the output of the AND gate is low?? What are the inputs of that gate connected to?

Bryce.

[MaV]

I feared that you'd ask this.
It's almost impossible to trace the three input lines for the AND, because they go directly underneath the 74LS153 and 74LS74 to the left of the 74LS11.

But if I'm not mistaken pin 11 of the 74LS11 goes (more or less, changing PCB side 2 times) straight to the RD pin of the connector.
Pin 10 seems to go to pin 17 of the PAL16L8. Very uncertain.
Pin 9 goes to pin 2 of the neighbouring 74LS153 and to pin 2 of the PAL16L8. The line is underneath the 74LS153, so I'm having a hard time making them out. Again very uncertain.

[MaV]

And the transistor is a BF240, so:

1 base -> pin 8 of the 74LS11
2 emitter -> MREQ
3 collector -> VCC

(The count on the datasheet is the other way around: 1=collector, etc. but I stick to our method to avoid confusion)


(now excuse me while I rest my bleeding eyes... )