Thanks for the manuals. TRB286IN.TD0 is a valid CP/M disk and contains TURBOW.COM and TURBOW.CMD.
Unfortunately, 6 other images appear to be broken when i try to mount them under DOS 3.10 ("bad unit error reading drive B"):

Code
X RBHDREM.TD0 
X SSIHDINS.TD0
X CLIKCLOK.TD0
X DOS310.TD0 
X DOS310SP.TD0 
X RBADAPKT.TD0 : crashes with "FATALERROR: Incorrect layout on track 0 head 0, expected_size=50000, current_size=88368 " 
(TD0 format violation?)

From my experience, it is better to read old disks on the original RX50 drive with the help of Jeff's RBIMG. This results in a plain sector image (no error info, though).

PC-HD drives tend to find errors on disks that are perfectly readable on a well-maintained RX50.

On another note: the CPU-ID program on RBDS31UT.IMD claims we "incorrectly allow interrupts after a change to SS" (see screenshot).

[Linked Image from dl.dropboxusercontent.com]

Old 8088 CPUs (before 1981) had this bug. Is that behaviour wanted / correct?

Assembler source from CPU ID 1.42
https://dl.dropboxusercontent.com/u/37819653/BANNISTER/CPUID.ASM

Hunt for FLG_CERR to find the code to exhibit the bug.

Last edited by Bavarese; 12/29/15 01:07 PM.