Search found 682 matches

by Arne
Wed Feb 24, 2021 5:36 pm
Forum: Hardware
Topic: Non populated RAM area
Replies: 12
Views: 363

Re: Non populated RAM area

ijor wrote: Wed Feb 24, 2021 4:07 pm No, disk DMA doesn't use the address bus. The address is private to MMU.
Now it becomes complicated. But thanks for the insight.
by Arne
Wed Feb 24, 2021 3:07 pm
Forum: Hardware
Topic: Non populated RAM area
Replies: 12
Views: 363

Re: Non populated RAM area

I agree with you about reading Shifter registers. But why handle DMA reads separately? They use address-bus, /AS and R/W, too. Isn't that enough? If /RDAT isn't combinatorial then it is probably a FSM clocked by CLK16 of the MMU. MMU will generate /DTACK in any case. So either another track to cut (...
by Arne
Wed Feb 24, 2021 7:42 am
Forum: Hardware
Topic: Non populated RAM area
Replies: 12
Views: 363

Re: Non populated RAM area

I'm not sure I understand the question. I would probably need a diagram to understand what are you doing. https://i.ibb.co/bRhJWpk/NewRDAT.gif Including some HDL pseudo-code. I guess I would not have to intercept the /G signal to both 74LS244. (...)It might produce some incompatibility issues in an...
by Arne
Tue Feb 23, 2021 6:07 pm
Forum: Hardware
Topic: Non populated RAM area
Replies: 12
Views: 363

Re: Non populated RAM area

Thanks for all the light. :cheers: For some unknown reason I totally omitted the 74LS244/373 combo from my thinking and that these are actively driving the "capacitive data" of the Shifter data bus onto the CPU data bus. Therefore the data-bus pullups on the CPU side are of no effect for this purpos...
by Arne
Tue Feb 23, 2021 12:42 pm
Forum: Hardware
Topic: Non populated RAM area
Replies: 12
Views: 363

Re: Non populated RAM area

So if I add a component that actively drives the bus the $4E75 value will be overwritten?
To me it seems strange that I do see even $0000 on the ST with 3K3 pull-ups! That would mean the level of the previous access did not recover to $FFFF into the next bus cycle at S6!
by Arne
Tue Feb 23, 2021 12:07 pm
Forum: Hardware
Topic: Non populated RAM area
Replies: 12
Views: 363

Re: Non populated RAM area

Wait. Seems to become confusing. This is contrary to what I observe on my STs. When reading memory above 1 MB (assuming a 1 MB machine) you get to see value other than $FFFF. I write $AA55 to $100000 and readback something different than $FFFF (pull-ups). I would expect $FFFF. Did a test on a IMP 10...
by Arne
Tue Feb 23, 2021 8:18 am
Forum: Hardware
Topic: Non populated RAM area
Replies: 12
Views: 363

Non populated RAM area

Hi folks, got an understanding problem: take a 1MB ST and poke some values in the area $100000..$1FFFFF (probably works for $3FFFFF as upper limit). If I read them back I would expect to read the pull-ups but I got values that are similar to the values I poked into the non-populated area. I know tha...
by Arne
Mon Feb 22, 2021 4:37 pm
Forum: Hardware
Topic: TT030 High resolution vertical stripes
Replies: 4
Views: 229

Re: TT030 High resolution vertical stripes

Can you upload a photo of the stripes on the screen? Do these stripes show as a (weird) colour jail-bar pattern on colour screen (VGA)? If so then I suggest to use a ST-RAM Test program or the diagnosis cartridge for the TT. Remove TT RAM (if available) and ST-RAm card. Then perform RAM-Test. Then a...
by Arne
Thu Feb 18, 2021 11:17 am
Forum: News & Announcements
Topic: Blitter version test
Replies: 29
Views: 1225

Re: Blitter version test

I do have such an IST Blitter (Datecode 8801). My father bought a new MST2 and it was delivered without Blitter. A couple of weeks later the dealer informed us that our Blitter IC arrived and it came with a crude A4 sheet of how to install it. I am very sure that it is this IST Blitter. DId you run...
by Arne
Thu Feb 18, 2021 9:02 am
Forum: News & Announcements
Topic: Blitter version test
Replies: 29
Views: 1225

Re: Blitter version test

I do have such an IST Blitter (Datecode 8801). My father bought a new MST2 and it was delivered without Blitter. A couple of weeks later the dealer informed us that our Blitter IC arrived and it came with a crude A4 sheet of how to install it. I am very sure that it is this IST Blitter.
by Arne
Wed Feb 17, 2021 9:28 pm
Forum: News & Announcements
Topic: Blitter version test
Replies: 29
Views: 1225

Re: Blitter version test

Finished my tests on a 4MB 1040STE TOS 2.06 machine and some Blitter gave a different result than $003F/$0040. But all my loose Blitters in the IC drawer come from MegaSTs. Is it granted that these Blitter will do their job in a 1040STE as expected? All I can say is that I tried one MST Blitter with...
by Arne
Wed Feb 17, 2021 8:44 pm
Forum: News & Announcements
Topic: Blitter version test
Replies: 29
Views: 1225

Re: Blitter version test

ijor wrote: Wed Feb 17, 2021 8:31 pm That's why we see $40 (64 in decimal) or $3F (63 decimal).
Expect to see much more strange values. No kidding!
I will put all my results in a PDF. Takes 5min. Comes by eMail.
by Arne
Wed Feb 17, 2021 8:10 pm
Forum: News & Announcements
Topic: Blitter version test
Replies: 29
Views: 1225

Re: Blitter version test

czietz wrote: Wed Feb 17, 2021 8:01 pm
Arne wrote: Wed Feb 17, 2021 7:54 pm Sent you a picture of my strange 1040STE-Blitter.
I am interested in that picture, too.
Probably the same as your No.2 setting. It a ST brand one. I am sure ijor will clarify things.
by Arne
Wed Feb 17, 2021 8:09 pm
Forum: News & Announcements
Topic: new Nova drivers
Replies: 199
Views: 92051

Re: new Nova drivers

@Idek: You know my opinion as we have talked about a similar topic one or two years ago. I saw your call for beta-testers but I was sure that a lot of people owning a Nova and using your drivers would "enlist". A more urgent follow-up post might have woken up people. Yes, these pseudo-experts do exi...
by Arne
Wed Feb 17, 2021 7:54 pm
Forum: News & Announcements
Topic: Blitter version test
Replies: 29
Views: 1225

Re: Blitter version test

Sent you a picture of my strange 1040STE-Blitter. I found another, very similar one in my IC drawer. It's an ST, too. Just three weeks younger (8945) and the Z-Number on the bottom right is different (Z927190). I am very sure that I removed it from a MegaST and not a STE. I do have two MM9092V (NS?)...
by Arne
Wed Feb 10, 2021 4:31 pm
Forum: Hardware
Topic: Installing the PAK68/3
Replies: 151
Views: 30506

Re: Installing the PAK68/3

TheNameOfTheGame wrote: Wed Feb 10, 2021 4:16 pm Arne, would you be be able to provide some pictures of your DMA buffer board?
You can find pictures in my shop. Which is closed for a week as I am leaving soon.
by Arne
Sun Feb 07, 2021 6:22 pm
Forum: Hardware
Topic: Dead falcon 030: help to repair
Replies: 17
Views: 875

Re: Dead falcon 030: help to repair

That looks much better. A simple Nullmodem cable, 3 wires (Rx<->Tx, Tx<->Rx, GND <->GND) will do. Settings in the terminal program are 9600bps, 8N1.
Please keep in mind that the testkit cannot analyze anything. It provides data and you have to do the rest.
by Arne
Sun Feb 07, 2021 4:01 pm
Forum: Hardware
Topic: Dead falcon 030: help to repair
Replies: 17
Views: 875

Re: Dead falcon 030: help to repair

So this is what I get on Pin 1 U58: https://i.ibb.co/17sL5bv/DS1-Z-Quick-Print1.png On Pin 2 U58: https://i.ibb.co/Q85wZvY/DS1-Z-Quick-Print2.png An on Pin 3 (/CE) of the ROM: https://i.ibb.co/mcYzhQX/DS1-Z-Quick-Print3.png If I understand well, while I do not have anything on pin 3 of ROM, cartridg...
by Arne
Sun Feb 07, 2021 12:53 pm
Forum: Hardware
Topic: Dead falcon 030: help to repair
Replies: 17
Views: 875

Re: Dead falcon 030: help to repair

Pin 2: +2.5V Please check with scope. I am sure that it is a 5V 50% duty cycle signal which results in 2.5V on a Voltmeter. But better be safe than sorry. Pin 3: 0V Flat, constant GND or some activity? Pin 4 is not an open-collector output (see schematic) and so I guess that CCLK is connected to so...
by Arne
Sun Feb 07, 2021 9:16 am
Forum: Hardware
Topic: Dead falcon 030: help to repair
Replies: 17
Views: 875

Re: Dead falcon 030: help to repair

Hi arthurlm, this is what I get on a F030 at pin 4 of U58: https://i.ibb.co/wgw0zR0/DS1-Z-Quick-Print1.png Pins 6,8,10,12 should be high (5V). And they are on my F030. Whats the voltage on the 74HC04's Vcc and GND? Do you see activity after power-up on pin 3 (/CE) of the TOS ROM? If there is no acti...
by Arne
Tue Jan 26, 2021 1:07 pm
Forum: Hardware
Topic: SpeedUp16+
Replies: 5
Views: 530

Re: SpeedUp16+

Last benchmark @16MHz + FastROM option activated: https://i.ibb.co/GHTxbv0/Speed-Up16-GB328.gif For some reason SpeedUp16+ doesn't like the Blitter. Tried two boards and two Blitter: first access to FDD from desktop gives two bombs. Bootsektor virus guardian is executed though. :? I may investigate...
by Arne
Wed Jan 20, 2021 12:31 pm
Forum: Hardware
Topic: SpeedUp16+
Replies: 5
Views: 530

Re: SpeedUp16+

Tried one Alt-Help snapshot utility I used for the QIndex screenshots and after CoreMark finished it throws two bombs as soon as I press [Alt]+[Help] 8O
So I took a camera:

Image

If I computed it correctly it's in the +15% range.
by Arne
Wed Jan 20, 2021 9:54 am
Forum: Hardware
Topic: SpeedUp16+
Replies: 5
Views: 530

SpeedUp16+

So folks, it's winter meaning: time-to-solder. 8) https://i.ibb.co/syjGj7Z/Speed-Up16.jpg Just for fun I revisited an old c't project from 1990: SpeedUp16. It's a simple 16MHz 68000 without cache: the poor man's booster. The original authors used some 74F00/02 for address decoding and some delay-lin...
by Arne
Fri Jan 15, 2021 4:05 pm
Forum: Hardware
Topic: ST reports sometimes only 256k
Replies: 2
Views: 163

Re: ST reports sometimes only 256k

How about starting SysInfo before and after that game and take a screenshot of what SysInfo reports?
by Arne
Tue Jan 05, 2021 12:40 pm
Forum: Hardware
Topic: PAK 68/3 Boot ROMs
Replies: 6
Views: 322

Re: PAK 68/3 Boot ROMs

So I did 16 measurements with /ROM2 and D[0..15]. Some measurements look dubious: https://i.ibb.co/vZJvCnP/Oszi1.gif (D1 in blue) And even more: https://i.ibb.co/16DrN8j/Oszi2.gif But if I see all of these hi-lo-hi spikes still as a '1' then the four accesses sum up to: $062E $0306 $ 00E0 $0030 I am...

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