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authorJulian Blake Kongslie2021-05-30 16:47:19 -0700
committerJulian Blake Kongslie2021-05-30 16:47:19 -0700
commitfa59c4b8e506e5503caa5b8b4499a3c1965800a5 (patch)
tree72ee8aa648524c57695ec624c447945e8460c58c /PLAN
parentWork in progress from May 9 (diff)
downloadnoncpu-wip.tar.xz
Work in progress from May 30wip
Diffstat (limited to '')
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1Don't ignore 6000 and 6001
2
3Add "interrupts enabled" flag
46000, 6001, 6002 should properly handle it
5 6000 - skip next instruction if interrupts are enabled; disable interrupts (we should probably do this immediately)
6 6001 - enable interrupts (after next instruction)
7 6002 - disable interrupts (we should probably do this immediately)
8
9Jules thinks clock is most likely interrupt source
10 pdp8 source tries to map clock interrupts to "real time" - we might want to mangle that to make it deterministic
11
12Sources of interrupts observed:
13 PTR flag is set from loader, might be ignorable
14 Memory management is poked from inside ISRs, might be ignorable (MMU should be optional)
15 TTO ready for output interrupt - this looks like a very likely candidate
16 TTI input ready interrupt - this looks like a very likely candidate
17 Looks like these happen even when there is no input available - might be caused by the program itself doing something a little funny