12 September 2008, 11:51 | #21 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
Cheers TC, the board is out of its case and all that's plugged in is the power and the video monitor
|
12 September 2008, 11:58 | #22 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
OK, changed agnus... Now get a light grey screen, then multicolour garbage on the monitor compressed down to about 10 scanlines!
Time to change/check denise... |
12 September 2008, 12:30 | #23 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
stranger and stranger - when J101 is on 1-2, and J500 closed, I get a normal power sequence which then reboots...
Remove 500 and I get the strange video effect Change 101 to 2 3, and with J500 closed I get a different strange video effect Remove J500 and I get a normal power sequence then reboot. Bloody weird. |
12 September 2008, 12:33 | #24 |
Amibay Senior Staff
Join Date: Feb 2008
Location: Cardiff / Wales
Posts: 1,302
|
@chiark,
I'm in work & dont have my A2000 schems handy to identify the jumpers for you, sorry my friend. Try BBoAH I think there maybe a summary there. Are you confident regarding the Agnus making good contact all the way round ??? TC |
12 September 2008, 12:55 | #25 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
Yep. And I've replaced the 8372 with an 8375... Same.
As soon as it's about to boot, or seek the drive, or display the workbench disk picture, it reboots. (Plugged a floppy in, and it does the same without seeking. Damn) |
12 September 2008, 13:05 | #26 | |
Amibay Senior Staff
Join Date: Feb 2008
Location: Cardiff / Wales
Posts: 1,302
|
Quote:
chiark I don't think the 8375 is pin compatible with the 8372 (someone correct me), You have replaced Gary too??? TC |
|
12 September 2008, 13:29 | #27 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
Gary?
yup. With known good ones. 8375 - right, i'll swap it back. Mine is an 8372a if that makes a difference? Every chip on this board worked perfectly in my other 2000... (And that has an 8371 agnus) |
12 September 2008, 13:35 | #28 |
Amibay Senior Staff
Join Date: Feb 2008
Location: Cardiff / Wales
Posts: 1,302
|
8372a is the PAL 1MB chip agnus.
Don't take my word for the 8375 not being pin compatible, I'm sure this is the case but hopefully Zetro will be along soon to confirm this for us.. Keep fighting you are making progress, Don't give up, but if you do send me the Mobo & I'll have a go for you.. TC |
12 September 2008, 13:54 | #29 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
Power LED is giving 6 flashes prior to the reset. Bugger, where's the reference for power LED flashes when you need it!?
EDIT: interesting, suggests the problem might be agnus related. Damn! Last edited by chiark; 12 September 2008 at 14:49. |
22 September 2008, 10:46 | #30 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
Just rereading this, I noticed rkauer's reference to the TTL flipflop...
Any more info, sir? |
22 September 2008, 18:39 | #31 |
I hate potatos and shirts
|
Maybe I can send you the TRM...
Amiga Schematics. Download the 4 A500_2000 TRM's (Technical Reference Manual) and look for "grey screen" - Agnus related-problem. |
22 September 2008, 19:00 | #32 | ||
I hate potatos and shirts
|
Quote:
Quote:
|
||
22 September 2008, 22:44 | #33 |
Ya' like it Retr0?
Join Date: Jul 2005
Location: United Kingdom
Age: 49
Posts: 9,768
|
Hello there my fellow forum chummies,
heres the results from my research on the 83xx Agni chips Code:
8375 [A500+ 390544-01] 8372 [A3000] 8372B 8370 pin# #desc #desc #desc #desc 01 DRD13 DRD13 DRD13 RD13 02 DRD12 DRD12 DRD12 RD12 03 DRD11 DRD11 DRD11 RD11 04 DRD10 DRD10 DRD10 RD10 05 DRD09 DRD09 DRD09 RD09 06 DRD08 DRD08 DRD08 RD08 07 DRD07 DRD07 DRD07 RD07 08 DRD06 DRD06 DRD06 RD06 09 DRD05 DRD05 DRD05 RD05 10 DRD04 DRD04 DRD04 RD04 11 DRD03 DRD03 DRD03 RD03 12 DRD02 DRD02 DRD02 RD02 13 DRD01 DRD01 DRD01 RD01 14 DRD00 DRD00 DRD00 RD00 15 +5V VCC VCC 16 _RESET _RESET _RESET _RESET 17 _INTR _INTR _INTR _INT3 18 DMAL _DMAL _DMAL _DMAL 19 _BLISS _BLISS _BLS _BLS 20 _BLIT _BLIT _BLIT _DBR 21 _WE _WE _WE _RRW 22 _RW _RW _RW _PRW 23 _REGEN _REGEN _REGEN _RGEN 24 _AS _AS _AS _AS 25 _RAMEN _RAMEN _RAMEN _RAMEN 26 RGA8 RGA8 RGA8 RGA8 27 RGA7 RGA7 RGA7 RGA7 28 RGA6 RGA6 RGA6 RGA6 29 RGA5 RGA5 RGA5 RGA5 30 RGA4 RGA4 RGA4 RGA4 31 RGA3 RGA3 RGA3 RGA3 32 RGA2 RGA2 RGA2 RGA2 33 RGA1 RGA1 RGA1 RGA1 34 28MHZ 28MHZ 28MHZ 28MHZ 35 A20 A20 A20 _XCLK (,A20) JP5 36 _CDAC _XCLKEN NC _XCLKEN 37 7MHZ _CDAC _CDAC _CDAC 38 CCKQ _7MHZ _7MHZ _7MHZ 39 CCK _CCKQ _CCKQ _CCKQ 40 14MHZ CCK _CCK _CCK 41 TEST PAL/NTSC TEST 42 CRA0 VSS1 VSS VSS 43 CRA1 DRA0 DRA0 MA0 44 CRA2 DRA1 DRA1 MA1 45 CRA3 DRA2 DRA2 MA2 46 CRA4 DRA3 DRA3 MA3 47 CRA5 DRA4 DRA4 MA4 48 CRA6 DRA5 DRA5 MA5 49 CRA7 DRA6 DRA6 MA6 50 CRA8 DRA7 DRA7 MA7 51 _LDS DRA8 DRA8 MA8 52 _UDS _LDS _LDS _LDS 53 _CASL _UDS _UDS _UDS 54 _CASU _CASL _CASL _CASL 55 CRA9 _cASU _CASU _CASU 56 DRA9 DRA9 _RAS1 57 _RAS0 _RAS _RAS _RAS0 58 _RAS1 VSS2 VSS VSS 59 A19 A19 A19 A19 60 A01 A01 A01 A01 61 A02 A02 A02 A02 62 A03 A03 A03 A03 63 A04 A04 A04 A04 64 A05 A05 A05 A05 65 A06 A06 A06 A06 66 A07 A07 A07 A07 67 A08 A08 A08 A08 68 A09 A09 A09 A09 69 A10 A10 A10 A10 70 A11 A11 A11 A11 71 A12 A12 A12 A12 72 A13 A13 A13 A13 73 A14 A14 A14 A14 74 A15 A15 A15 A15 75 A16 A16 A16 A16 76 A17 A17 A17 A17 77 A18 A18 A18 A18 78 _LPEN _LPEN _LPEN _LP 79 _VSYNC _VSYNC _VSYNC _VSY 80 _CSYNC _CSYNC _CSYNC _CSY 81 _HSYNC _HSYNC _HSYNC _HSY 82 VSS VSS VSS 83 DRD15 DRD15 DRD15 DRD15 84 DRD14 DRD14 DRD14 DRD14 8375 SRC: A500 PLUS MAINTENANCE MANUAL 8372 SRC: "FATAGNUS PRESENT DANS LES AMIGA 300" .GIF 8372B SRC: "8372B-AGNUS_PIN.TXT" 8370 SRC: "8370-AGNUS-PLCC.PNG" The most common is the A500+ which has a pin shift on pin 40. my other thoughts that could be a problem. If the board has suffered a battery leak, then its likely that its changed the chemical property of some of the metal alloy that makes up some of them sockets. For instance, I was very VERY fortunate to be given an A2000 from G-H in the AmiBay Recycle Bin, and also very fortunate that my friend r0jaws was able to pick it up. however the battery had caused server damage to not so much the board itself but to the CPU and its connector. Fortunately the CPU Connector just had a nasty scum of green, alas not so could be said for the CPU, in fact it had reacted so bad on one side that the pins were as weak as paper and as you touched them they collapsed off the chip. (fear not that lovely Motorola cpu has a new home as my keychain ) so I would say double check the IC sockets closest to the battery for any metal fatigue and replace the socket. with the gray / white screens you are sooooo damn close. good luck my friend |
23 September 2008, 10:23 | #34 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
Cheers Z, that's the thing: it's close. I can almost feel the success already
The 3 track repair to the kickstart chip area is not neat, but works... The weird thing is my other 2000 has an 8372A in it and that works with the 8375. if I put the 8372a in the "new" machine, I get nothing at all. Agni are bloody weird. |
23 September 2008, 10:45 | #35 | |
Ya' like it Retr0?
Join Date: Jul 2005
Location: United Kingdom
Age: 49
Posts: 9,768
|
Quote:
man thats frustrating, I thought the 8372a was a 2MB NTSC Agni, I could be wrong, back to my studdy there are some OLD revisions of A2000 motherboards that have thier Ram configured in such a way that the 2MB Agni just wont work, if I remember reading the file from aminet correctly. what revision of board is it? LOL, I have just asked a question I fear I may fail on, had I of re-read the thread I would of seen it I am sure. |
|
23 September 2008, 10:53 | #36 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
Now there's the strange thing. I *think* they're both 6.3 revision boards: one is brown, has suffered a severe battery leak, was owned by a tinkerer who has soldered switches on a few jumpers and is generally a bit of a mess; the other is green, has the octal latches to the right of the cpu on a daughterboard (upside down) for no real reason, has suffered a slight battery leak, and looks very clean and was owned by a butcher who it appears tried to swap a kickstart by inserting a screwdriver *under* the chip SOCKET and forcing it out, damaging tracks in the process.
The brown one works fine. The green one is in the reset loop... So, so close... I have pics, but they're not with me: will post later! |
23 September 2008, 11:16 | #37 | |
Amibay Senior Staff
Join Date: Feb 2008
Location: Cardiff / Wales
Posts: 1,302
|
Quote:
That's why I have always hesitated from inserting an 8375 in place of an 8372A in my A500 / A2000 AGNI can confuse the mind and soul TC |
|
23 September 2008, 11:20 | #38 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
This must be a Thursday. I never could get the hang of Thursdays.
(Oh hang on, it's Tuesday... Damn!) |
23 September 2008, 11:28 | #39 |
Amibay Senior Staff
Join Date: Feb 2008
Location: Cardiff / Wales
Posts: 1,302
|
|
24 September 2008, 11:53 | #40 |
Needs a life
Join Date: Jan 2008
Location: England
Posts: 1,707
|
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
Thread Tools | |
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Which Agnus chips did the good old A500 have? | Quickbeam | Retrogaming General Discussion | 30 | 07 August 2023 12:19 |
Good values for Amiga PSU:s - noise problem. | ascp | support.Hardware | 5 | 21 November 2012 00:27 |
Amiga 2000 black screen | JACK98 | support.Hardware | 30 | 26 July 2010 01:18 |
Amitek A500 PSU any good?? | PowerPie5000 | support.Hardware | 5 | 16 December 2009 13:42 |
Free to good home Goliath PSU in UK only | sarek2k | MarketPlace | 7 | 07 June 2006 10:05 |
|
|