<div dir="ltr">I have some troubles running a known working XXDP V2.2 image in SimH on a 11/23 (without +), 11/03, 11/04, 11/05 and 11/20.<div><br></div><div>I have tested this on a PDP-11/44 and a PDP-11/23+ CPU and it works fine. Testing the same image in SimH on 11/23+ and 11/44 config with 64kbyte memory starts the XXDP fine.</div><div><br></div><div>
<p class=""><a href="https://dl.dropboxusercontent.com/u/96935524/xxdp.dsk">https://dl.dropboxusercontent.com/u/96935524/xxdp.dsk</a></p></div><div><br></div><div>Now I have to be honest. I am not entirely sure which CPU configs should be able to run XXDP V2.2 (Small Monitor). </div><div><br></div><div>But I basically thought that switching to 11/23 (without plus) should work fine since it is very similar to the plus. Just removing the two SLUs and the Boot ROMs would make it identical as far as I can see it.</div><div><br></div><div>But it doesn't start.</div><div><br></div><div><div>sim> b rq0</div><div><br></div><div><br></div><div>HALT instruction, PC: 000104 (JMP SP)</div></div><div><br></div><div>Doing a continue actually makes it to boot:</div><div><br></div><div><div>sim> c</div><div><br></div><div>NOT ENOUGH MEMORY TO BOOT XXDP-XM</div><div><br></div><div><br></div><div><br></div><div>BOOTING UP XXDP-SM SMALL MONITOR</div><div><br></div><div><br></div><div><br></div><div>XXDP-SM SMALL MONITOR - XXDP V2.2</div><div>REVISION: C0</div><div>BOOTED FROM DU0</div><div>28KW OF MEMORY</div><div>NON-UNIBUS SYSTEM</div><div><br></div><div>RESTART ADDR: 152010</div><div>TYPE "H" FOR HELP</div><div><br></div><div>.</div></div><div><br></div><div>But it is not entirely happy since the very simple GKAAA0 cpu test that runs fine in 11/23+ mode fails.</div><div><br></div><div><div>.R GKAAA0</div><div>GKAAA0.BIC</div><div><br></div><div>HALT instruction, PC: 000104 (JMP SP)</div><div>sim> </div></div><div><br></div><div>I know that SimH is not supposed to be able to run the diags but what is the difference on a SimH level between 11/23 and 11/23+ that causes one to run and the other not?</div><div><br></div><div>Then I tested some other CPUs:</div><div><br></div><div>11/34, 11/40, 11/44, 11/45, 11/60, 11/70, 11/73, 11/83, 11/84, 11/93 </div><div><br></div><div>The all can start XXDP V2.2 (SM) and run GKAAA0 fine.</div><div><br></div><div>But </div><div><br></div><div>11/03 and 11/23 give me the halt. In the 11/03 case it is not possible to do a continue.</div><div><br></div><div>Testing 11/04, 11/05 and 11/20 all give the same result. It never boots but gets stuck in some loop where it seems to poll the console.</div><div><br></div><div><div>Step expired, PC: 150674 (BPL 150750)</div><div>sim> s</div><div><br></div><div>Step expired, PC: 150750 (MOV (SP)+,R1)</div><div>sim> s</div><div><br></div><div>Step expired, PC: 150752 (RTS PC)</div><div>sim> s</div><div><br></div><div>Step expired, PC: 151006 (TST R0)</div><div>sim> s</div><div><br></div><div>Step expired, PC: 151010 (BEQ 151002)</div><div>sim> s</div><div><br></div><div>Step expired, PC: 151002 (JSR PC,150664)</div><div>sim> s</div><div><br></div><div>Step expired, PC: 150664 (CLR R0)</div><div>sim> s</div><div><br></div><div>Step expired, PC: 150666 (MOV R1,-(SP))</div><div>sim> s</div><div><br></div><div>Step expired, PC: 150670 (TSTB @#177560)</div><div>sim> s</div><div><br></div><div>Step expired, PC: 150674 (BPL 150750)</div><div>sim> s</div></div><div><br></div><div><br></div><div>SimH is built from head:</div><div><br></div><div><div>sim> sh ver</div><div>PDP-11 simulator V4.0-0 Beta</div><div><span class="" style="white-space:pre"> </span>Simulator Framework Capabilities:</div><div><span class="" style="white-space:pre"> </span>32b data</div><div><span class="" style="white-space:pre"> </span>32b addresses</div><div><span class="" style="white-space:pre"> </span>Ethernet Packet transports:PCAP:NAT:UDP</div><div><span class="" style="white-space:pre"> </span>Idle/Throttling support is available</div><div><span class="" style="white-space:pre"> </span>Virtual Hard Disk (VHD) support</div><div><span class="" style="white-space:pre"> </span>Asynchronous I/O support</div><div><span class="" style="white-space:pre"> </span>FrontPanel API Version 1</div><div><span class="" style="white-space:pre"> </span>Host Platform:</div><div><span class="" style="white-space:pre"> </span>Compiler: GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.2.76)</div><div><span class="" style="white-space:pre"> </span>Simulator Compiled: Dec 27 2015 at 17:51:17</div><div><span class="" style="white-space:pre"> </span>Memory Access: Little Endian</div><div><span class="" style="white-space:pre"> </span>Memory Pointer Size: 64 bits</div><div><span class="" style="white-space:pre"> </span>Large File (>2GB) support</div><div><span class="" style="white-space:pre"> </span>RegEx support for EXPECT commands</div><div><span class="" style="white-space:pre"> </span>OS clock resolution: 1ms</div><div><span class="" style="white-space:pre"> </span>Time taken by msleep(1): 2ms</div><div><span class="" style="white-space:pre"> </span>OS: Darwin localhost 12.5.0 Darwin Kernel Version 12.5.0: Sun Sep 29 13:33:47 PDT 2013; root:xnu-2050.48.12~1/RELEASE_X86_64 x86_64</div><div><br></div><div> git commit id: ea4d9a16</div></div><div><br></div><div>Tested SimH 3.9 and it does the same</div><div><br></div><div>11/04, 11/05 and 11/20 all lack MMU if this has to do with it. But 11/03 also lack MMU and is not behaving the same, although not booting. The 11/23 has the MMU but is still not booting while the almost identical 11/23+ boots just fine.</div><div><br></div><div>Well. If someone can help me sort this out I am would be happy. My next step is to try to boot the same image on a real 11/04, 11/03 and a 11/23 (without +) to see if that works. Just need to toggle in that long bootstrap.</div><div><br></div><div>/Mattis</div><div><br></div></div>