iRMX Versions (2004)

                              iRMX I            iRMX II          iRMX III          iRMX for Windows
Current release               I.8.1             II.4.1           III.2             2.0B
First released                1980              1985             1989              July 1992
Nucleus size                  14-26K            39K              56K               N/A
Full OS size w/o Network      308K              378K             550K              4MB w/Windows & Network Dev. User
Network size                  158K              220K             230K              230K
Remote boot                   Multibus I        Multibus I       Multibus I        PC/AT, EISA, MCA
Prommable                     Yes               Yes              Yes               No
Max. segment size             64K               64K              4GB               4GB
Max. number of objects        64K               8192             8192              8192
SBM/SDB support               PROM              PROM             Softloaded        Softloaded
Source-level debugger         Soft Scope 86     Soft Scope I     Soft Scope III    Soft Scope III
Multibus II support           Class B ZAP       Built in         Built in          Loadable job
CPU mode                      Real              Protected        Protected         Protected
CPU type                      8086              80286, 386, 486  386, 486, Pentium 386, 486, Pentium
Max. application size         1MB               16MB             4GB               4GB
Number of priority levels     255               255              255               255
DOS as VM86 task              No                No               No                Yes
Windows 3.1                   No                No               No                Yes

iRMX II operating system

Offered on 80286, 80386 and 80486 family of microprocessors. It executes in a special mode of the
microprocessor called Protected Virtual Address Mode or PVAM. Unlike the iRMX I operating system,
the tokens for iRMX II objects are selectors and refers to an entry in a descriptor table.
iRMX II supports Multibus I, Multibus II and can also be stored in prom for embedded designs. It
was also offered for a IBM PC-AT platform called the Intel System 120 as a special way to have
either iRMX or DOS botted from the same media.