HEX R/W D7 D6 D5 D4 D3 D2 D2 D0 function
17 ---------+-----+------------------------+------------------------
18 0000 D D D D D D D D XCOORD
19 0001 D D D D D D D D YCOORD
20 0002 D D D BIT MODE DATA
21 ---------+-----+------------------------+------------------------
22 0003-033F D D D D D D D D Working RAM
23 0340-3D3F D D D D D D D D Screen RAM
24 3D40-3FFF D D D D D D D D Working RAM
25 ---------+-----+------------------------+------------------------
26 4000-403F R D D D D D D D D EARD* read from non-volatile memory
27 ---------+-----+------------------------+------------------------
28 5000 R D coin AUX (CTRLD* set low)
29 5000 R D coin LEFT (CTRLD* set low)
30 5000 R D coin RIGHT (CTRLD* set low)
31 5000 R D SLAM (CTRLD* set low)
32 5000 R D SPARE (CTRLD* set low)
33 5000 R D SPARE (CTRLD* set low)
34 5000 R D COCKTAIL (CTRLD* set low)
35 5000 R D SELF-TEST (CTRLD* set low)
36 5000 R D D D D HDIR (CTRLD* set high)
37 5000 R D D D D VDIR (CTRLD* set high)
38 ---------+-----+------------------------+------------------------
39 5001 R D SHIELD 2
40 5001 R D SHIELD 1
41 5001 R D FIRE 2
42 5001 R D FIRE 1
43 5001 R D SPARE (CTRLD* set low)
44 5001 R D START 2
45 5001 R D START 1
46 5001 R D VBLANK
47 ---------+-----+------------------------+------------------------
48 6000-600F W D D D D base_ram*
49 6200-621F W D D D D D D D D COLORAM*
50 6400 W INTACK*
51 6600 W D D D D EARCON
52 6800 W D D D D D D D D STARTLG (planet frame)
53 6A00 W WDOG*
54 ---------+-----+------------------------+------------------------
55 6C00 W D START LED 1
56 6C01 W D START LED 2
57 6C02 W D TBSWP*
58 6C03 W D SPARE
59 6C04 W D CTRLD*
60 6C05 W D COINCNTRR
61 6C06 W D COINCNTRL
62 6C07 W D PLANET
63 ---------+-----+------------------------+------------------------
64 6E00-6E3F W D D D D D D D D EARWR*
65 7000-701F D D D D D D D D IOS2* (Pokey 2)
66 7800-781F D D D D D D D D IOS1* (Pokey 1)
67 8000-EFFF R D D D D D D D D ROM
68 -----------------------------------------------------------------
Well I was following the seqeunce given in the manual, which is Address lines, then Data lines, then Ram etc..
I'll run the bus sigs now, and see what I get.
Thanks,
Kevin2009/11/25 John Robertson <jrr@flippers.com>Yes.Kevin Moore wrote:
Hi all, in my quest to learn more about using these tools, I've actually
come up with a problem, and could use a little explanation.
I'm working on a liberator board, and was using the atari cat box. The first
two tests in the liberator manual have you check address lines. Well those
checked out good. Next was the Data lines. This is where things fell apart,
and I'm not sure what I'm seeing.
Punch in address 0000, and write AA check the D0-D7 lines going to the ls245
well half the incoming lines are the wrong state, and the output of the
ls245 is non existent. Ie pins 2-9 have no output.
So I hook up my fluke 9010a thinking there may be something wrong with the
catbox, since this is the first time I've used it. Did the same basic setup
wddis grounded, and Ö0 Ö2 shorted together. Do a write to 0000 with AA and
use my logic probe to check. Same results.
Am I to assume Bad memory at location 0000.??
Did you do the BUS Test first? That will show if any address or data lines are misbehaving.
If BUS Test is OK, and you get this problem for RAM @ 0000h, then try the next RAM set - say @ 0800h or 1000h (if RAM present - check Memory Map). If other RAM all checks OK, or ANY RAM checks OK, then the RAM @ 0000h is certainly suspect.
If the RAM is 4-bit, then which bits are locked will tell you which RAM to replace.
John :-#)#
--
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, VideoGames)
www.flippers.com "Old pinballers never die, they just flip out"
_______________________________________________
Techtoolslist mailing list
Techtoolslist@flippers.com
http://seven.pairlist.net/mailman/listinfo/techtoolslist
FTP site is: ftp://ftp.flippers.com/TTL/TestEquipment
Archive site: http://seven.pairlist.net/pipermail/techtoolslist/