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Added process information definitions.

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Russell-S-Harper 2019-03-29 22:22:15 -04:00
parent 7e3d87425d
commit 6f9818441f
1 changed files with 24 additions and 6 deletions
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30
common/common.h
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@ -88,13 +88,19 @@ _F_N = 32 ; if Rr < 0.0 (after TST)
_F_O = 64 ; if overflow (after arithmetic operations)
_F_U = 128 ; if underflow (after arithmetic operations)
; register I7 maintains locations of process and allocated memory
; register I7 maintains locations of code and allocated real memory addresses
_CRL = _I7 ; code low and high bytes
_CRH = _CRL + 1
_ARL = _CRH + 1 ; allocated low and high bytes
_ARH = _ARL + 1
_CR = _CRL ; code real memory address
_AR = _ARL ; allocated real memory address
; register I8 maintains process information for context switching
_PST = _I8 ; current process status
_PSI = _PST + 1 ; process stack index to save/restore
_PD0 = _PSI + 1 ; pending
_PD1 = _PD0 + 1
_PSO = _PSI + 1 ; offset to running processes table
_PSF = _PSO + 1 ; initial running process status PPPCCCLF
; register I9 saves/restores processor status
; (dd cc bb aa) aa: accumulator, bb: index X, cc: index Y, dd: processor status
@ -112,10 +118,22 @@ _RSS = _R0 ; register stack size
; for context switching, _R0 to _RS + _RSS - 1 needs to be saved and restored
; this should comprise two pages or 512 bytes
_PR = _RS + _RSS ; running processes
_PRS = FN_FX - _PR ; running process size
; the following are common process table and system & user functions
; 32 bytes of page two
; process information in the middle of page two
_RP = _RS + _RSS ; running processes table
_RPS = FN_FX - _RP ; running process table size
; process information indices
_RPV_I = 0 ; 4 bytes virtual memory address
_RPR_I = _RPV_I + 4 ; 2 bytes real memory address
_RPS_I = _RPR_I + 2 ; 1 byte size of program (in pages) including allocated memory
_RPF_I = _RPS_I + 1 ; 1 byte status PPPCCCLF / P priority / C counter / L loaded / F finished
_RPE = _RPF_I + 1 ; size of running process entry
_RPL = _RPS / _RPE ; number of running processes limit
; last 32 bytes of page two
FN_FX = $300 - 2 * 16 ; list of system and user functions
; function constants