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ID Category [?] Severity [?] Reproducibility Date Submitted Last Update
08511 Core Major Always 30 days ago 23 days ago
Tester pnp2084 View Status Public Platform MAME (Official Binary)
Assigned To Resolution Open OS Windows 10/11 (64-bit)
Status [?] Driver
Version 0.249 Fixed in Version Build 64-bit
Fixed in Git Commit Github Pull Request #
Summary 08511: trs80l2: SuperUtility 3 boot fails because of false sync
Description The attached su3v30-perl.mfi (from the su3v30.dsk DMK file) fails to boot on the TRS-80 Model I.

The problem is the RADDR commands see false FM 0xFE sync bytes in the MFM data of Track 1.
As a result, the code retries the RADDR a few times until it fails.

The following breakpoints can be used to see the RADDR results.
bp 452d - $c0 RADDR
bp 452a - see 4a00 (HL) accumulate bogus results

The groups of 6 bytes at 0x4a00 are:
"FE FE FF F2 B1 F5" - false
"20 20 20 02 76 DE" - real
"30 30 30 02 2D 69" - real
"25 25 25 02 DE 9E" - real
"E5 EF F5 C6 DE 77" - false
"F3 F1 FE BE 5F 77" - false
Steps To Reproduce The follow command will display "DIsk Error _"
mame trs80l2 -flop1 su3v30-perl.mfi
Additional Information Possibly the WD17xx state machine should enforce some "sync zero" bits before detecting the FM IDAM.
Github Commit
Regression Version
Affected Sets / Systems trs80l2
Attached Files
zip file icon (293,565 bytes) 30 days ago Uploaded by pnp2084
SuperUtility 3.0 for TRS-80 Model I
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