m_thompson
Veteran Member
I am trying to get FOCAL running on the RICM's PDP-9. There are four different versions available, one for each of the ADSS operating system versions. We have DECtape, so we run the Keyboard Monitor version of ADSS. There are two different versions of FOCAL for the ADSS Keyboard Monitor, one for an 8k memory system, and one if you have 12k or more memory. With more than 8k of memory you use the GLOAD command to invoke the LOADER and then load the FOCAL binary and libraries, and then run FOCAL. With 8k of memory there is not enough room for the LOADER, FOCAL binary, symbol tables, and the libraries. There is of course another version of FOCAL that is invoked with the EXECUTE command that loads the FOCAL.XCT file. I suspect that the FOCAL.XCT file is a main FOCAL program with many overlays to make the memory footprint smaller. The CHAIN command is used to convert a relocatable binary into an XCT file. I can get the XCT version of FOCAL to run on the RICM's 8k PDP-9. I got to to print "HELLO WORLD", but found that none of the math works. I tried the same system configuration using Simh, and got the same results. I enabled the EAE option in the Simh processor and FOCAL math worked. The PDP-15 FOCAL manual says that FOCAL uses the FORTRAN IV math libraries. I believe that there are both EAE and non-EAE versions of the F4 math libraries, so it looks like the small memory Keyboard Monitor version of FOCAL that we have is linked to the EAE version of the F4 libraries. We have the MACRO source code for FOCAL, so we could build a new FOCAL.XCT file from the source and link it to the non-EAE F4 library. That swill be an adventure.