Hi Will, This seems to be a legitimate problem given the inconsistencies that you are seeing.
Please create an issue at: https://github.com/simh/simh/issues outlining what you've said below and that will be used to track this to a resolution. Thanks. - Mark On Monday, December 28, 2015 at 3:58 PM, Will Senn wrote: > In looking at bootloaders I have observed some interesting SimH behavior and I > am hoping y'all might have something to say about it. > > In sum, is it possible to deposit values directly into the I/O registers from > the > sim> prompt, if so, can you provide an example using the RK or RP command > register? > > I have tried the following in the default PDP-11/73 with 4MB Memory: > > PDP-11 simulator V4.0-0 Beta git commit id: 0f43551d > sim> d 17777410 177540 > Address space exceeded > > This would seem to answer the question in the negative. However, if I then put > info into the buffer by typing in some machine code and executing it directly: > > PDP-11 simulator V4.0-0 Beta git commit id: 0f43551d > sim> id 10000-10006 > 10000: 012737 > 10002: 177540 > 10004: 177410 > 10006: 000000 > sim> g 10000 > > HALT instruction, PC: 010010 (HALT) > > and then reference the I/O buffer in SimH: > > sim> ex 17777410 > 17777410: 177540 > > The I/O buffer now appears to be available for examine. > > sim> ex 17777410 > 17777410: 177540 > > And for deposit: > sim> d 17777410 177530 > sim> ex 17777410 > 17777410: 177530 > > Interestingly, Address space exceeded doesn't appear to be a problem. > What is going on with SimH's PDP-11 simulation. Is the device not really > "there" > until it is referenced from a machine code program, or is the > 17777410 address not initialized until the device is accessed, or what? _______________________________________________ Simh mailing list [email protected] http://mailman.trailing-edge.com/mailman/listinfo/simh
