[Ql-Users] Memory contention (CPU / ULA)
Hi all, I am working on some timing critical routines for standard QL w/wo SandyQboard 512 (no GC, no Aurora). Do you know how is memory shared between CPU and ULA? Do you know how (if at all) is memory delayed when you need to access videoram at the same time ULA is accessing it? Is there any emulator emulating that feature? Thanks, Jan -- www.icq.atlas.cz/ ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] Memory contention (CPU / ULA)
Palenicek Jan wrote: I am working on some timing critical routines for standard QL w/wo SandyQboard 512 (no GC, no Aurora). Do you know how is memory shared between CPU and ULA? Do you know how (if at all) is memory delayed when you need to access videoram at the same time ULA is accessing it? I'm no hardware guy, but I'm pretty sure the ULA locks ALL internal memory during screen refresh, i.e. depending on model (EU/US) 50 or 60 times per second. The CPU cannot access anything at all during these times. Some memory expansions like the Trump Card are not as limited, you do not get any delays accessing the extended RAM there. Is there any emulator emulating that feature? No emulator comes anywhere near a cycle-exact emulation. Emulators providing QL-like speed only arbitrarily slow down the emulation to roughly equal the speed. Marcel ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] SBASIC extras
Looking at a list of SBASIC extensions created with an EXTRAS command, there are 3 extensions I noticed that I don't know what they do. Not in my (admittedly old) manual. Anyone know? CHK_HEAP (Some form of heap check suggested by the name) HOME_CSET (presumably something to do with Home Thing) PAR_WAIT (presumably something to do with parallel port) HOME_CSET [job_ID], directory$ Part of SMSQ/E, documented in extras_new_home_info_txt in the SMSQ/E source files: Set the current directory for the job. The directory must the a valid directory. CHK_HEAP Part of SMSQ/E, documented in QPC_Keywords and possibly elsewhere: This enables debugging routines in the SBASIC core for SBASIC development and should not be used by any users. Thank you. -- Dilwyn Jones ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
