Prop hub RAM fail - bad bit!
Peter Jakacki
Posts: 10,193
in Propeller 1
Never thought I'd see this but it seems I have a perfectly brand new Prop chip on a board that kept failing to accept some Tachyon code. It seems I have at least one hub memory location where there is a bad bit.
Perhaps I should run memory tests on all chips?
If I run this one-liner you can see the partial results where bit 2 ($04) never sets.
Perhaps I should run memory tests on all chips?
If I run this one-liner you can see the partial results where bit 2 ($04) never sets.
$100 0 DO CR I .BYTE SPACE I $5FDD C! $5FDD C@ .BYTE LOOP
00 00
01 01
02 02
03 03
04 00
05 01
06 02
07 03
08 08
09 09
0A 0A
0B 0B
0C 08
0D 09
0E 0A
0F 0B
10 10
11 11
12 12
13 13
14 10
Comments
: MEMTEST ADO I C@ I 8 0 DO I MASK OVER C! DUP C@ I MASK <> IF CR DUP .WORD SPACE I . THEN LOOP DROP I C! LOOP ; $2000 $5000 MEMTEST 5009 2 500D 2 5019 2 501D 2 5029 2 502D 2 5039 2 503D 2 5049 2 504D 2 5059 2 505D 2 5069 2 506D 2 5079 2 507D 2 5089 2 508D 2 5099 2 509D 2 50A9 2 50AD 2 50B9 2 50BD 2 50C9 2 50CD 2 50D9 2 50DD 2 50E9 2 50ED 2 50F9 2 50FD 2 5109 2 510D 2 5119 2 511D 2 5129 2 512D 2 5139 2 513D 2 5149 2 514D 2 5159 2 515D 2 5169 2 516D 2 5179 2 517D 2 5189 2 518D 2 5199 2 519D 2 51A9 2 51AD 2 51B9 2 51BD 2 51C9 2 51CD 2 51D9 2 51DD 2 51E9 2 51ED 2 51F9 2 51FD 2 5209 2 520D 2 5219 2 521D 2 5229 2 522D 2 5239 2 523D 2 5249 2 524D 2 5259 2 525D 2 5269 2 526D 2 5279 2 527D 2 5289 2 528D 2 5299 2 529D 2 52A9 2 52AD 2 52B9 2 52BD 2 52C9 2 52CD 2 52D9 2 52DD 2 52E9 2 52ED 2 52F9 2 52FD 2 5309 2 530D 2 5319 2 531D 2 5329 2 532D 2 5339 2 533D 2 5349 2 534D 2 5359 2 535D 2 5369 2 536D 2 5379 2 537D 2 5389 2 538D 2 5399 2 539D 2 53A9 2 53AD 2 53B9 2 53BD 2 53C9 2 53CD 2 53D9 2 53DD 2 53E9 2 53ED 2 53F9 2 53FD 2 5409 2 540D 2 5419 2 541D 2 5429 2 542D 2 5439 2 543D 2 5449 2 544D 2 5459 2 545D 2 5469 2 546D 2 5479 2 547D 2 5489 2 548D 2 5499 2 549D 2 54A9 2 54AD 2 54B9 2 54BD 2 54C9 2 54CD 2 54D9 2 54DD 2 54E9 2 54ED 2 54F9 2 54FD 2 5509 2 550D 2 5519 2 551D 2 5529 2 552D 2 5539 2 553D 2 5549 2 554D 2 5559 2 555D 2 5569 2 556D 2 5579 2 557D 2 5589 2 558D 2 5599 2 559D 2 55A9 2 55AD 2 55B9 2 55BD 2 55C9 2 55CD 2 55D9 2 55DD 2 55E9 2 55ED 2 55F9 2 55FD 2 5609 2 560D 2 5619 2 561D 2 5629 2 562D 2 5639 2 563D 2 5649 2 564D 2 5659 2 565D 2 5669 2 566D 2 5679 2 567D 2 5689 2 568D 2 5699 2 569D 2 56A9 2 56AD 2 56B9 2 56BD 2 56C9 2 56CD 2 56D9 2 56DD 2 56E9 2 56ED 2 56F9 2 56FD 2 5709 2 570D 2 5719 2 571D 2 5729 2 572D 2 5739 2 573D 2 5749 2 574D 2 5759 2 575D 2 5769 2 576D 2 5779 2 577D 2 5789 2 578D 2 5799 2 579D 2 57A9 2 57AD 2 57B9 2 57BD 2 57C9 2 57CD 2 57D9 2 57DD 2 57E9 2 57ED 2 57F9 2 57FD 2 5809 2 580D 2 5819 2 581D 2 5829 2 582D 2 5839 2 583D 2 5849 2 584D 2 5859 2 585D 2 5869 2 586D 2 5879 2 587D 2 5889 2 588D 2 5899 2 589D 2 58A9 2 58AD 2 58B9 2 58BD 2 58C9 2 58CD 2 58D9 2 58DD 2 58E9 2 58ED 2 58F9 2 58FD 2 5909 2 590D 2 5919 2 591D 2 5929 2 592D 2 5939 2 593D 2 5949 2 594D 2 5959 2 595D 2 5969 2 596D 2 5979 2 597D 2 5989 2 598D 2 5999 2 599D 2 59A9 2 59AD 2 59B9 2 59BD 2 59C9 2 59CD 2 59D9 2 59DD 2 59E9 2 59ED 2 59F9 2 59FD 2 5A09 2 5A0D 2 5A19 2 5A1D 2 5A29 2 5A2D 2 5A39 2 5A3D 2 5A49 2 5A4D 2 5A59 2 5A5D 2 5A69 2 5A6D 2 5A79 2 5A7D 2 5A89 2 5A8D 2 5A99 2 5A9D 2 5AA9 2 5AAD 2 5AB9 2 5ABD 2 5AC9 2 5ACD 2 5AD9 2 5ADD 2 5AE9 2 5AED 2 5AF9 2 5AFD 2 5B09 2 5B0D 2 5B19 2 5B1D 2 5B29 2 5B2D 2 5B39 2 5B3D 2 5B49 2 5B4D 2 5B59 2 5B5D 2 5B69 2 5B6D 2 5B79 2 5B7D 2 5B89 2 5B8D 2 5B99 2 5B9D 2 5BA9 2 5BAD 2 5BB9 2 5BBD 2 5BC9 2 5BCD 2 5BD9 2 5BDD 2 5BE9 2 5BED 2 5BF9 2 5BFD 2 5C09 2 5C0D 2 5C19 2 5C1D 2 5C29 2 5C2D 2 5C39 2 5C3D 2 5C49 2 5C4D 2 5C59 2 5C5D 2 5C69 2 5C6D 2 5C79 2 5C7D 2 5C89 2 5C8D 2 5C99 2 5C9D 2 5CA9 2 5CAD 2 5CB9 2 5CBD 2 5CC9 2 5CCD 2 5CD9 2 5CDD 2 5CE9 2 5CED 2 5CF9 2 5CFD 2 5D09 2 5D0D 2 5D19 2 5D1D 2 5D29 2 5D2D 2 5D39 2 5D3D 2 5D49 2 5D4D 2 5D59 2 5D5D 2 5D69 2 5D6D 2 5D79 2 5D7D 2 5D89 2 5D8D 2 5D99 2 5D9D 2 5DA9 2 5DAD 2 5DB9 2 5DBD 2 5DC9 2 5DCD 2 5DD9 2 5DDD 2 5DE9 2 5DED 2 5DF9 2 5DFD 2 5E09 2 5E0D 2 5E19 2 5E1D 2 5E29 2 5E2D 2 5E39 2 5E3D 2 5E49 2 5E4D 2 5E59 2 5E5D 2 5E69 2 5E6D 2 5E79 2 5E7D 2 5E89 2 5E8D 2 5E99 2 5E9D 2 5EA9 2 5EAD 2 5EB9 2 5EBD 2 5EC9 2 5ECD 2 5ED9 2 5EDD 2 5EE9 2 5EED 2 5EF9 2 5EFD 2 5F09 2 5F0D 2 5F19 2 5F1D 2 5F29 2 5F2D 2 5F39 2 5F3D 2 5F49 2 5F4D 2 5F59 2 5F5D 2 5F69 2 5F6D 2 5F79 2 5F7D 2 5F89 2 5F8D 2 5F99 2 5F9D 2 5FA9 2 5FAD 2 5FB9 2 5FBD 2 5FC9 2 5FCD 2 5FD9 2 5FDD 2 5FE9 2 5FED 2 5FF9 2 5FFD 2 okThat's what I was thinking since it's a brand new chip although I'm not worried about the chip itself but I do want to run some memory tests on this batch of prototypes to see if any of them have a problem.
In some cases failure analysis would have to be performed to determine the cause of the failure. Given that Parallax chips are often subjected to conditions exceeding the max handling/operating conditions (basing this on forum posts), they would need to determine when this would be appropriate.
Standard operating conditions of 3.3V with a 6MHz oscillator input x16 -> 96MHz but also tested these at 48MHz and still with the same problem. The fault is repeatable and consistent.
What is the date code?
Meanwhile Parallax can see if you uncovered a test hole - I don't believe that they use MEMBIST. If that's true and they load functional code to perform the memory testing, then perhaps they could effectively run it remotely with you.