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authorJulian Blake Kongslie2022-01-30 16:35:02 -0800
committerJulian Blake Kongslie2022-01-30 16:36:00 -0800
commit61b644866337d8db517beb8f089ef4311b83bd39 (patch)
tree2d2f66b4036f7ecca75a70f52386f7c8472ad7fd /PLAN
parentImplement DF and IF, and Dep and Exam switches. (diff)
downloadnoncpu-61b644866337d8db517beb8f089ef4311b83bd39.tar.xz
Working focal!
It turns out that indirect jumps don't preincrement. The interpreter is almost unreadable at this point due to debugging messages. Sorry.
Diffstat (limited to '')
-rw-r--r--PLAN15
1 files changed, 2 insertions, 13 deletions
diff --git a/PLAN b/PLAN
index e9689e2..2e32e77 100644
--- a/PLAN
+++ b/PLAN
@@ -1,13 +1,2 @@
1Turn on blinkenlights from the PDP core 1Instrument simh to have deterministic input timing (stuffed input queue)
2 2Instrument simh to have diagnostic messages about interrupt sources and terminal/keyboard/interrupt enable flags
3Implement remaining TTY output instructions
4
5Jules thinks clock is most likely interrupt source
6 pdp8 source tries to map clock interrupts to "real time" - we might want to mangle that to make it deterministic
7
8Sources of interrupts observed:
9 PTR flag is set from loader, might be ignorable
10 Memory management is poked from inside ISRs, might be ignorable (MMU should be optional)
11 TTO ready for output interrupt - this looks like a very likely candidate
12 TTI input ready interrupt - this looks like a very likely candidate
13 Looks like these happen even when there is no input available - might be caused by the program itself doing something a little funny