ack/plat/cpm/libsys/_trap.s
2019-06-11 20:02:03 +02:00

91 lines
1.8 KiB
ArmAsm

#
! $Source$
! $State$
! $Revision$
#
#include "asm.h"
.define .trp
.define EARRAY, ERANGE, ESET, EIOVFL, EFOVFL, EFUNFL, EIDIVZ, EIDIVZ
.define EFDIVZ, EIUND, EFUND, ECONV, ESTACK, EHEAP, EILLINS, EODDZ
.define ECASE, EMEMFLT, EBADPTR, EBADPC, EBADLAE, EBADMON, EBADLIN, EBADGTO
.define EUNIMPL
! Trap routine
! Expects trap number in A, and must be called directly from the code
! where execution should resume (for those traps which support it).
! Just returns if trap has to be ignored.
! Otherwise it calls a user-defined trap handler if provided.
! When no user-defined trap handler is provided or when the user-defined
! trap handler causes a new trap, a message is printed
! and control is returned to the monitor.
EARRAY = 0
ERANGE = 1
ESET = 2
EIOVFL = 3
EFOVFL = 4
EFUNFL = 5
EIDIVZ = 6
EFDIVZ = 7
EIUND = 8
EFUND = 9
ECONV = 10
ESTACK = 16
EHEAP = 17
EILLINS = 18
EODDZ = 19
ECASE = 20
EMEMFLT = 21
EBADPTR = 22
EBADPC = 23
EBADLAE = 24
EBADMON = 25
EBADLIN = 26
EBADGTO = 27
EUNIMPL = 63 ! unimplemented em-instruction called
.trp:
mov a,l
cpi 16
jnc 3f ! jump if trap cannot be ignored
! check if trap has to be ignored
xchg ! de = trap number
lhld .ignmask
push h ! hl = set to be tested
push d
call .inn2 ! de = 1 if bit is set, 0 otherwise
mov a,e
rar
jnc 3f ! jump if trap should not be ignored
pop h ! remove trap number
ret ! OGEN DICHT EN ... SPRING!!!
3:
.define .trapproc
.trapproc = . + 1
lxi h, 0 ! user defined trap handler held inline here
mov a,l
ora h
jz 1f ! jump if there was not
xra a
sta .trapproc ! .trapproc := 0
sta .trapproc+1
lxi d,2f
push d
pchl ! call user defined trap handler
2:
pop d
ret
1:
lxi d, text
mvi c, 9 ! write $-terminated string
call 0x0005
rst 0 ! abend
.sect .rom
text: .ascii "TRAP!\r\n$"