Hi Guys, Sorry for the BIG post ;-) This might be a bit of a *noob* silly question, but I'm having issues using my 9010a and 68000 pod doing a Rom Checksum on a working outrun board (to teach myself how to use it) Now.... I've used my 6502 pod in the past, with no issues whatsoever to test rams and roms, and am familiar how the 8 bit systems work, as I've programmed for them in the past/present..... BUT... This is the first time I've used the 68000 Pod, and I'm unsure of a couple of things..... ( I've no experience working with 16 bit cpu's ).... Initially I was wondering what had happened to A0 , and then after having a quick read up, it appears that its only used internally and the 'external' adresses go up in steps of 2 (hence A1>Axx).... Looking at Quater Arcades Scripting tool...It shows me a memory map of outrun.... based on Mame.... http://tech.quarterarcade.com/Tech/CodeGenerator/Default.aspx?g=1996&set=out... ########################################################################### RAM 0 - 3FFFF RAM1 Calculated RAM. Confirm. [edit] [del] 60000 - 67FFF RAM2 Calculated RAM. Confirm. [edit] [del] 60900 - 60907 RAM3 Calculated RAM. Confirm. [edit] [del] 100000 - 10FFFF RAM4 Calculated RAM. Confirm. [edit] [del] 110000 - 110FFF RAM5 Calculated RAM. Confirm. [edit] [del] 120000 - 121FFF RAM6 Calculated RAM. Confirm. [edit] [del] 130000 - 130FFF RAM7 Calculated RAM. Confirm. [edit] [del] 140030 - 140031 RAM8 Calculated RAM. Confirm. [edit] [del] 200000 - 23FFFF RAM9 Calculated RAM. Confirm. [edit] [del] 260000 - 267FFF RAM10 Calculated RAM. Confirm. [edit] [del] ROM 0 - FFFF BFDB 10380a Generated ROM test [edit] [del] 1 - 10000 18E 10382a Generated ROM test [edit] [del] 20000 - 2FFFF 90 10381a Generated ROM test [edit] [del] 20001 - 30000 731B 10383a Generated ROM test [edit] [del] ############################################################################### Right.... Down to some testing...... I'm not generating scripts and dumping to the fluke or doing any fancy tricks just yet, I'm just doing the standard Fast Ram / Rom tests from the keyboard to get a feel of the thing,get up to speed and how it works..... Rams.... ###### 60000-67FFF Tests the 4 Ram IC's next to CPU 1 - These are 8k chips and there are four of them - so that makes 32K x 8 Bits in my books (and from 8 bit experience - x0000 > x7fff is 32k of '8-bit' Ram Space.... I punch in Ram Fast Test.... 60000 > 67FFF and after a while it passes OK so this seems to work great..... I can also access the CPU2's Rams and test those too via shared memory.OK... (cant recall now, but I think at 260000 > 267FFFF) Roms.... ###### Here is where I am struggling..... I'll just cover two of the roms to keep things simple.... 0 - FFFF - Checksum = BFDB - Rom Name 10380a 1 - 10000 - Checksum = 18E - Rom Name 10382a Now these are 64k Roms x 8 bits each...... but I'm unable to run ROM tests here..... It fails on checksum....!!!!!!!!!! eg...I punch in... Rom Test 0 > FFFF - CSum BFDB , I get Fail and Rom Test 1 >10000 - CSum 18E - Fail.... I pretty well gave up here !!!!! (this is a working board with the right roms fitted). ############# If memory is accessed in steps of 2 (due to missing out A0) surely the CPU address range for the 1st 64k rom would be 0 > 1FFFF , so I should really tell the fluke to test 0 > 1FFFF (bfdb) and 1 > 20000 (18e) .... is this right ? or am I just going nuts and getting my bits all mixed up ? ( I've not tested this yet as my header socket needs swapping and repairing ).... If I'm wrong.... then what SHOULD I be punching in to the ROM test to test these two roms ???? (eg .. is there a step setting that I should be telling it ?) The Rams and Roms sit on the Bus in Pairs.... Top Pairs on Schems are D0>D7 and Bottom Pairs are D8>D15... Rams are A1>A13 (13 Lines - 8k ) and Roms are A1>A16 (16 lines - 64K) Any handy hints or tips or help to steer me in the right direction would be very much appreciated please, Thanks.... Regards, Colin _______________________________________________ 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/