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StarInfo/Fletcher/AllWCD/WSWI-Help
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
| Tape/disk: | Home » Recent acquisitions » Acorn ADFS disks » adfs_AcornUser_199604.adf » Features |
| Filename: | StarInfo/Fletcher/AllWCD/WSWI-Help |
| Read OK: | ✔ |
| File size: | 367D bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
WimpSWIVe 0.04 (27 Apr 1995)
==================================
NewerLook needs to trap Wimp_ SWIs in order to provide its new error
windows. The only official way to trap SWIs is to trap the SWI hardware
vector, but even this is not recommended. It takes much code to implement
properly in all circumstances (about 30K of source code for Desktop Hacker),
and can slow the machine down, quite considerably when there are multiple
claimants.
It is, however, possible to trap Wimp_ SWIs by providing another module
with the same SWI chunk and names. This method is much quicker and easier,
but is rather dodgy. One of the problems is that only one module can do this
at a time. So if NewerLook had a module that used this method, it wouldn�t
work properly when another program tried to do the same thing.
Thus, I have separated the trapping code from the action code (which resides
in another module), and released this module separately. It can manage SWI
claims and releases dynamically, a bit like vectors. You can use it in your
own programs if you like. Here�s how.
Because WimpSWIVe uses the Wimp�s SWI chunk, it cannot provide its own
SWIs. Instead, it communicates using a Wimp SWI, namely Wimp_RegisterFilter.
Here is the WimpSWIVe specification for Wimp_RegisterFilter.
| Wimp_RegisterFilter
| (SWI &400F5)
|
| Used by the Filter Manager to register or deregister a filter
| OR used to register SWI claims and releases with WimpSWIVe
|
On entry: | R0 = reason code:
| &49575357 (�WSWI�) for WimpSWIVe operation (see below)
| anything else for filter operation (see RISC OS 3
| Programmers� Reference Manual, page 3-224)
| R1 = SWI word:
| bits 0-5 : offset in SWI chunk of SWI to claim/release
| bits 6-29: undefined, leave unset
| bit 30 : high priority if set, else low priority
| bit 31 : claim if set, else release
| R2 = value to be passed in R12 on entry to code
| R3 = address of SWI pre-trapping code, or 0 if none needed
| R4 = address of SWI post-trapping code, or 0 if none needed
|
On exit: | Registers preserved
|
Interrupts: | Interrupts may be enabled
| Fast interrupts may be enabled
|
Processor: | Processor is in SVC mode
|
Reentrancy: | SWI is not re-entrant
|
Use: | In WimpSWIVe usage, this SWI is used to claim or release SWIs.
| The pre-trapping code specified is called before the SWI is
| called, and the post-trapping code afterwards.
|
| High-priority pre-code is called before low priority pre-code.
| (And high-priority post-code is called after low priority
| post-code.) This is important because one piece of pre-code
| could intercept a SWI call before another bit got a look in.
| You should use high-priority code for monitoring and register-
| altering code. If your pre-code is at all likely to intercept
| a SWI, you must use low-priority code. In effect, low-priority
| code is 'closer' to the real SWI.
|
| Pre-trapping code conditions:
|
| On entry: R0-R8 = registers passed to SWI
| R9 = offset into chunk of SWI called
| R12 = value specified when RegisterFilter called
| R13 = full, descending stack
| R14 = return address
| On exit: R0-R8 = may be altered to change effect of SWI
| R9 = preserved, or -1 to intercept SWI
|
| Pre-trapping code is entered in SVC mode, with interrupts
| disabled. If R9=-1 on exit, the SWI is not called. Instead,
| any outstanding post-code is called, and the caller is returned
| to with the supplied R0-R8 and PSR flags. An error may be
| signified by pointing R0 to an error block and setting the V
| flag on return as normal, when intercepting. (See footnote 1.)
|
| If more than one client has claimed a SWI, it is the earliest
| claimant�s pre-trapping code that is called last - new
| claimants take priority (though high-priority always beats low-
| priority, of course). If interception occurs, any post-trapping
| code for claims where the pre-trapping code (if any) has
| already been executed are also executed. In effect, you are
| guaranteed that you will get a post-trap event if you have had
| a pre-trap. (See footnote 2.)
|
|
| Post-trapping code conditions:
|
| On entry: R0-R8 = registers passed back from SWI
| R9 = offset into chunk of SWI called
| R12 = value specified when RegisterFilter called
| R13 = full, descending stack
| R14 = return address
| On exit: R0-R8 = may be altered to change perceived results
| PSR flags may be altered to change perceived results
| (for example to flag an error).
|
| Post-trapping code is entered in SVC mode, with interrupts
| disabled.
|
| If more than one client has claimed a SWI, it is the earliest
| claimant�s post-trapping code that is called first, subject
| to priority. (See footnote 2.)
|
| Remember that your post-trapping code may well be entered in an
| error condition. So check whether the V flag is set on entry,
| and return if it is (if you return with the S flag (MovS Pc,R14
| or LdmFd R13!,{...,Pc}^, the flags are unaffected). Never
| change the PSR flags by accident.
|
|
| Unlike OS_Claim, this SWI will not remove previous instances of
| claims with the same values. The release routine also only
| removes one instance of the values at a time.
|
| Claiming the Wimp_RegisterFilter SWI only traps the normal
| filter-based use of the SWI. Under no circumstances should you
| call Wimp_RegisterFilter with WimpSWIVe usage in your trapping
| code. If you really must claim or release a SWI when some other
| SWI is executed, use a CallBack to do it. (See the RISC OS 3
| Programmers� Reference Manual, page 1-319.)
|
| NB: You should NOT post-trap Wimp_Poll or Wimp_StartTask.
| (Or Wimp_PollIdle.) Trapping Wimp_Poll is easy anyway, using
| the old filter system.
|
Errors: | Bad value passed to WIMP in R0
| if WimpSWIVe is not loaded, the attempt to use this SWI in
| the WimpSWIVe manner will cause this error
| Bad WimpSWIVe release
| releasing a SWI you had not claimed generates this error
| No room in RMA
| is also possible but highly unlikely.
|
Footnote 1 - Re-entrancy issues:
Re-entrancy is nae problem if you only use pre-trapping or only use post-
trapping - you can either be re-entrant by using a stack to store stuff, or
prevent re-entering using a threaded flag (and unless you call a SWI, you
cannot be re-entered anyway). If you use both, but the post-code always does
the same regardless of the pre-code, you're all right too.
But if you use both at once and the action of post depends on something
that happened in pre (for example if you have pre to check the reason code
is worth bothering with in the post-trap code), it is slightly more complex.
It's quite possible that calling a Wimp SWI may cause another Wimp SWI to be
called, especially when you consider there can be many WimpSWIVe claimants.
Consider:
SWI Wimp_Thing called
WimpSWIVe claimant 1 pre-traps SWI
Claimant 1 store data for SWI 1 in workspace
WimpSWIVe claimant 2 pre-traps SWI
Claimant 2 executes Wimp_Gubbins
Wimp_Gubbins causes Wimp_Thing to be called
WimpSWIVe claimant 1 pre-traps SWI
Claimant 1 stores data for SWI 2 in workspace
WimpSWIVe claimant 2 pre-traps SWI
Claimant 2 is threaded, and so does nothing
WimpSWIVe executes real SWI Wimp_Thing
WimpSWIVe claimant 2 post-traps SWI
Claimant 2 is threaded, and so does nothing
WimpSWIVe claimant 1 post-traps SWI
Claimant 1 performs action on results, dependent on workspace
which holds data for SWI 2
WimpSWIVe returns
WimpSWIVe executes real Wimp_Thing SWI
WimpSWIVe claimant 2 post-traps SWI
Claimant 2 does whatever it needs to with results
WimpSWIVe claimant 1 post-traps SWI
Claimant 1 performs action on results, dependent on workspace
which holds data for SWI *2*
WimpSWIVe returns
As you can see, there is a lot of scope here for things going wrong, and
horrible clashes where one WimpSWIVe program may make another go wrong,
potentially rather messily.
There are two things you can do about it. Perhaps the best is to store a
'count' of post-traps to ignore. This count should be zero initially, and
should be incremented first when your pre-trap code detects that post-
trapping should do something effective. It should also be incremented every
time the pre-trap code is entered with the count non-zero. The post trap code
then checks the count on entry. If the count is zero, it returns doing
nothing. If the count is one or greater, the count is decremented. If the
count is one exactly one, the effect of the post-trap is activated. There's
an example of this in the EigenSysInfo source.
This is fine normally, but it makes the trapping code only affect the first
SWI to be affected (the "outermost" affected SWI). If you want to be truly
re-entrant, you'd have to store values on the stack to indicate whether to
post-trap on each call. And you couldn't use the SVC stack, so you'd have to
use a private stack. And you'd have to revert to the above behaviour if the
stack was filled up. Therefore, I don't reckon it's worth bothering with,
especially as allowing true re-entrancy opens the door to recursive problems
(Wimp_Thing calls Wimp_Gubbins calls Wimp_Thing calls Wimp_Gubbins etc.) too.
Sorry about the complexity of this footnote. Relax. You don't need to
bother about all this horrid stuff, usually. :-)
Footnote 2:
Your post-trap code will only be called if the SWI does return. This might
not happen if the SWI is one that doesn't return (but I can't think of any
Wimp_ SWIs that don't), or if a serious error happens. The latter should
never happen in a perfect system, but bugs happen and the SWI being trapped
might branch through zero or something. With the Wimp, though, a crash at
this stage often means there is something very wrong with the whole desktop
and everything is going to die anyway, so your module failing to post-trap
is unlikely to annoy the user much. :-)
-----------------------------------------------------------------------------
This module is supplied with some example programs:
- 3DErrorWindow. This is a useful module that replaces the WIMP�s error
windows with its own Risc PCable 3D ones (it needs 3DErrorWindow$Path to
point to a directory containing Templates and Messages - you can find one
in Sources.ErrorWind) using pre-trapping (usually with interception). The
windows could do with the NewerLook 'titlejoint' sprite in the wimp pool,
along with the Risc PC error system sprites.
- EigenSysInfo. This is a pretty useless one that changes Wimp_ReadSysInfo
2 always to return 24 or 22, and return the latter if Log2YEig<2 (the
WIMP returns 22 if Log2YEig==Log2XEig, which is silly). It also goes
'beep' if the Wimp returned a different value to it (try mode 22 and the
like). It�s not particularly great because most programs don�t take any
notice of ReadSysInfo (partly because of its aforementioned bobbinsness)
but it shows you how to pre-trap and post-trap SWIs at the same time (as
in footnote 1).
The source for these programs, along with the full source to WimpSWIVe and
some resources for 3DErrorWindow are to be found in the Sources directory.
However, these programs require BAX to be loaded for them to compile. BAX is
DoggySoft�s Basic Assembler Extension, which provides all ARM3, ARM6, FPA10
and coprocessor instructions, along with many useful pseudo-instructions.
You can get BAX from good PD libraries and Arcade, Digital Databank and
Furzefield Hq BBSs. It�s essential for Basic assembler programmers!
If you use this module in a program, be sure to RMEnsure version 0.04 or
later - versions 0.01 and 0.02 are NewerLook quick releases with bugs in
post-trapping, and version 0.03 do not feature high-priority SWI trapping,
as well as sometimes entering pre-code with interrupts enabled.
This module is freeware. Free free to distribute and use. To contact me -
for praise, to suggest new bits to add, or (heaven forbid) to report a bug,
please write to:
Andrew Clover,
7 Blackhorse Crescent,
Amersham,
Bucks.,
HP6 6HP.
Or phone me on 01494-431916, send a fax on 01494-675878, send some email to
ajc@doggysft.demon.co.uk or even telex on 83675 Brit G.
00000000 57 69 6d 70 53 57 49 56 65 20 20 20 20 20 20 20 |WimpSWIVe |
00000010 30 2e 30 34 20 28 32 37 20 41 70 72 20 31 39 39 |0.04 (27 Apr 199|
00000020 35 29 0a 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d |5).=============|
00000030 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d |================|
00000040 3d 3d 3d 3d 3d 0a 0a 0a 20 4e 65 77 65 72 4c 6f |=====... NewerLo|
00000050 6f 6b 20 6e 65 65 64 73 20 74 6f 20 74 72 61 70 |ok needs to trap|
00000060 20 57 69 6d 70 5f 20 53 57 49 73 20 69 6e 20 6f | Wimp_ SWIs in o|
00000070 72 64 65 72 20 74 6f 20 70 72 6f 76 69 64 65 20 |rder to provide |
00000080 69 74 73 20 6e 65 77 20 65 72 72 6f 72 0a 77 69 |its new error.wi|
00000090 6e 64 6f 77 73 2e 20 54 68 65 20 6f 6e 6c 79 20 |ndows. The only |
000000a0 6f 66 66 69 63 69 61 6c 20 77 61 79 20 74 6f 20 |official way to |
000000b0 74 72 61 70 20 53 57 49 73 20 69 73 20 74 6f 20 |trap SWIs is to |
000000c0 74 72 61 70 20 74 68 65 20 53 57 49 20 68 61 72 |trap the SWI har|
000000d0 64 77 61 72 65 0a 76 65 63 74 6f 72 2c 20 62 75 |dware.vector, bu|
000000e0 74 20 65 76 65 6e 20 74 68 69 73 20 69 73 20 6e |t even this is n|
000000f0 6f 74 20 72 65 63 6f 6d 6d 65 6e 64 65 64 2e 20 |ot recommended. |
00000100 49 74 20 74 61 6b 65 73 20 6d 75 63 68 20 63 6f |It takes much co|
00000110 64 65 20 74 6f 20 69 6d 70 6c 65 6d 65 6e 74 0a |de to implement.|
00000120 70 72 6f 70 65 72 6c 79 20 69 6e 20 61 6c 6c 20 |properly in all |
00000130 63 69 72 63 75 6d 73 74 61 6e 63 65 73 20 28 61 |circumstances (a|
00000140 62 6f 75 74 20 33 30 4b 20 6f 66 20 73 6f 75 72 |bout 30K of sour|
00000150 63 65 20 63 6f 64 65 20 66 6f 72 20 44 65 73 6b |ce code for Desk|
00000160 74 6f 70 20 48 61 63 6b 65 72 29 2c 0a 61 6e 64 |top Hacker),.and|
00000170 20 63 61 6e 20 73 6c 6f 77 20 74 68 65 20 6d 61 | can slow the ma|
00000180 63 68 69 6e 65 20 64 6f 77 6e 2c 20 71 75 69 74 |chine down, quit|
00000190 65 20 63 6f 6e 73 69 64 65 72 61 62 6c 79 20 77 |e considerably w|
000001a0 68 65 6e 20 74 68 65 72 65 20 61 72 65 20 6d 75 |hen there are mu|
000001b0 6c 74 69 70 6c 65 0a 63 6c 61 69 6d 61 6e 74 73 |ltiple.claimants|
000001c0 2e 0a 0a 20 49 74 20 69 73 2c 20 68 6f 77 65 76 |... It is, howev|
000001d0 65 72 2c 20 70 6f 73 73 69 62 6c 65 20 74 6f 20 |er, possible to |
000001e0 74 72 61 70 20 57 69 6d 70 5f 20 53 57 49 73 20 |trap Wimp_ SWIs |
000001f0 62 79 20 70 72 6f 76 69 64 69 6e 67 20 61 6e 6f |by providing ano|
00000200 74 68 65 72 20 6d 6f 64 75 6c 65 0a 77 69 74 68 |ther module.with|
00000210 20 74 68 65 20 73 61 6d 65 20 53 57 49 20 63 68 | the same SWI ch|
00000220 75 6e 6b 20 61 6e 64 20 6e 61 6d 65 73 2e 20 54 |unk and names. T|
00000230 68 69 73 20 6d 65 74 68 6f 64 20 69 73 20 6d 75 |his method is mu|
00000240 63 68 20 71 75 69 63 6b 65 72 20 61 6e 64 20 65 |ch quicker and e|
00000250 61 73 69 65 72 2c 0a 62 75 74 20 69 73 20 72 61 |asier,.but is ra|
00000260 74 68 65 72 20 64 6f 64 67 79 2e 20 4f 6e 65 20 |ther dodgy. One |
00000270 6f 66 20 74 68 65 20 70 72 6f 62 6c 65 6d 73 20 |of the problems |
00000280 69 73 20 74 68 61 74 20 6f 6e 6c 79 20 6f 6e 65 |is that only one|
00000290 20 6d 6f 64 75 6c 65 20 63 61 6e 20 64 6f 20 74 | module can do t|
000002a0 68 69 73 0a 61 74 20 61 20 74 69 6d 65 2e 20 53 |his.at a time. S|
000002b0 6f 20 69 66 20 4e 65 77 65 72 4c 6f 6f 6b 20 68 |o if NewerLook h|
000002c0 61 64 20 61 20 6d 6f 64 75 6c 65 20 74 68 61 74 |ad a module that|
000002d0 20 75 73 65 64 20 74 68 69 73 20 6d 65 74 68 6f | used this metho|
000002e0 64 2c 20 69 74 20 77 6f 75 6c 64 6e 91 74 0a 77 |d, it wouldn.t.w|
000002f0 6f 72 6b 20 70 72 6f 70 65 72 6c 79 20 77 68 65 |ork properly whe|
00000300 6e 20 61 6e 6f 74 68 65 72 20 70 72 6f 67 72 61 |n another progra|
00000310 6d 20 74 72 69 65 64 20 74 6f 20 64 6f 20 74 68 |m tried to do th|
00000320 65 20 73 61 6d 65 20 74 68 69 6e 67 2e 0a 0a 20 |e same thing... |
00000330 54 68 75 73 2c 20 49 20 68 61 76 65 20 73 65 70 |Thus, I have sep|
00000340 61 72 61 74 65 64 20 74 68 65 20 74 72 61 70 70 |arated the trapp|
00000350 69 6e 67 20 63 6f 64 65 20 66 72 6f 6d 20 74 68 |ing code from th|
00000360 65 20 61 63 74 69 6f 6e 20 63 6f 64 65 20 28 77 |e action code (w|
00000370 68 69 63 68 20 72 65 73 69 64 65 73 0a 69 6e 20 |hich resides.in |
00000380 61 6e 6f 74 68 65 72 20 6d 6f 64 75 6c 65 29 2c |another module),|
00000390 20 61 6e 64 20 72 65 6c 65 61 73 65 64 20 74 68 | and released th|
000003a0 69 73 20 6d 6f 64 75 6c 65 20 73 65 70 61 72 61 |is module separa|
000003b0 74 65 6c 79 2e 20 49 74 20 63 61 6e 20 6d 61 6e |tely. It can man|
000003c0 61 67 65 20 53 57 49 0a 63 6c 61 69 6d 73 20 61 |age SWI.claims a|
000003d0 6e 64 20 72 65 6c 65 61 73 65 73 20 64 79 6e 61 |nd releases dyna|
000003e0 6d 69 63 61 6c 6c 79 2c 20 61 20 62 69 74 20 6c |mically, a bit l|
000003f0 69 6b 65 20 76 65 63 74 6f 72 73 2e 20 59 6f 75 |ike vectors. You|
00000400 20 63 61 6e 20 75 73 65 20 69 74 20 69 6e 20 79 | can use it in y|
00000410 6f 75 72 0a 6f 77 6e 20 70 72 6f 67 72 61 6d 73 |our.own programs|
00000420 20 69 66 20 79 6f 75 20 6c 69 6b 65 2e 20 48 65 | if you like. He|
00000430 72 65 91 73 20 68 6f 77 2e 0a 0a 20 42 65 63 61 |re.s how... Beca|
00000440 75 73 65 20 57 69 6d 70 53 57 49 56 65 20 75 73 |use WimpSWIVe us|
00000450 65 73 20 74 68 65 20 57 69 6d 70 91 73 20 53 57 |es the Wimp.s SW|
00000460 49 20 63 68 75 6e 6b 2c 20 69 74 20 63 61 6e 6e |I chunk, it cann|
00000470 6f 74 20 70 72 6f 76 69 64 65 20 69 74 73 20 6f |ot provide its o|
00000480 77 6e 0a 53 57 49 73 2e 20 49 6e 73 74 65 61 64 |wn.SWIs. Instead|
00000490 2c 20 69 74 20 63 6f 6d 6d 75 6e 69 63 61 74 65 |, it communicate|
000004a0 73 20 75 73 69 6e 67 20 61 20 57 69 6d 70 20 53 |s using a Wimp S|
000004b0 57 49 2c 20 6e 61 6d 65 6c 79 20 57 69 6d 70 5f |WI, namely Wimp_|
000004c0 52 65 67 69 73 74 65 72 46 69 6c 74 65 72 2e 0a |RegisterFilter..|
000004d0 48 65 72 65 20 69 73 20 74 68 65 20 57 69 6d 70 |Here is the Wimp|
000004e0 53 57 49 56 65 20 73 70 65 63 69 66 69 63 61 74 |SWIVe specificat|
000004f0 69 6f 6e 20 66 6f 72 20 57 69 6d 70 5f 52 65 67 |ion for Wimp_Reg|
00000500 69 73 74 65 72 46 69 6c 74 65 72 2e 0a 0a 0a 20 |isterFilter.... |
00000510 20 20 20 20 20 20 20 20 20 20 20 7c 20 20 20 20 | | |
00000520 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000540 20 20 20 20 20 20 20 20 20 57 69 6d 70 5f 52 65 | Wimp_Re|
00000550 67 69 73 74 65 72 46 69 6c 74 65 72 0a 20 20 20 |gisterFilter. |
00000560 20 20 20 20 20 20 20 20 20 7c 20 20 20 20 20 20 | | |
00000570 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000590 20 20 20 20 20 20 20 20 20 20 20 20 20 20 28 53 | (S|
000005a0 57 49 20 26 34 30 30 46 35 29 0a 20 20 20 20 20 |WI &400F5). |
000005b0 20 20 20 20 20 20 20 7c 0a 20 20 20 20 20 20 20 | |. |
000005c0 20 20 20 20 20 7c 20 55 73 65 64 20 62 79 20 74 | | Used by t|
000005d0 68 65 20 46 69 6c 74 65 72 20 4d 61 6e 61 67 65 |he Filter Manage|
000005e0 72 20 74 6f 20 72 65 67 69 73 74 65 72 20 6f 72 |r to register or|
000005f0 20 64 65 72 65 67 69 73 74 65 72 20 61 20 66 69 | deregister a fi|
00000600 6c 74 65 72 0a 20 20 20 20 20 20 20 20 20 20 20 |lter. |
00000610 20 7c 20 4f 52 20 75 73 65 64 20 74 6f 20 72 65 | | OR used to re|
00000620 67 69 73 74 65 72 20 53 57 49 20 63 6c 61 69 6d |gister SWI claim|
00000630 73 20 61 6e 64 20 72 65 6c 65 61 73 65 73 20 77 |s and releases w|
00000640 69 74 68 20 57 69 6d 70 53 57 49 56 65 0a 20 20 |ith WimpSWIVe. |
00000650 20 20 20 20 20 20 20 20 20 20 7c 0a 20 20 4f 6e | |. On|
00000660 20 65 6e 74 72 79 3a 20 7c 20 52 30 20 3d 20 72 | entry: | R0 = r|
00000670 65 61 73 6f 6e 20 63 6f 64 65 3a 0a 20 20 20 20 |eason code:. |
00000680 20 20 20 20 20 20 20 20 7c 20 20 20 20 20 20 20 | | |
00000690 20 20 26 34 39 35 37 35 33 35 37 20 28 94 57 53 | &49575357 (.WS|
000006a0 57 49 95 29 20 66 6f 72 20 57 69 6d 70 53 57 49 |WI.) for WimpSWI|
000006b0 56 65 20 6f 70 65 72 61 74 69 6f 6e 20 28 73 65 |Ve operation (se|
000006c0 65 20 62 65 6c 6f 77 29 0a 20 20 20 20 20 20 20 |e below). |
000006d0 20 20 20 20 20 7c 20 20 20 20 20 20 20 20 20 61 | | a|
000006e0 6e 79 74 68 69 6e 67 20 65 6c 73 65 20 66 6f 72 |nything else for|
000006f0 20 66 69 6c 74 65 72 20 6f 70 65 72 61 74 69 6f | filter operatio|
00000700 6e 20 28 73 65 65 20 52 49 53 43 20 4f 53 20 33 |n (see RISC OS 3|
00000710 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 20 |. | |
00000720 20 20 20 20 20 20 20 50 72 6f 67 72 61 6d 6d 65 | Programme|
00000730 72 73 91 20 52 65 66 65 72 65 6e 63 65 20 4d 61 |rs. Reference Ma|
00000740 6e 75 61 6c 2c 20 70 61 67 65 20 33 2d 32 32 34 |nual, page 3-224|
00000750 29 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 |). | |
00000760 52 31 20 3d 20 53 57 49 20 77 6f 72 64 3a 0a 20 |R1 = SWI word:. |
00000770 20 20 20 20 20 20 20 20 20 20 20 7c 20 20 20 20 | | |
00000780 20 20 20 20 20 62 69 74 73 20 30 2d 35 20 3a 20 | bits 0-5 : |
00000790 6f 66 66 73 65 74 20 69 6e 20 53 57 49 20 63 68 |offset in SWI ch|
000007a0 75 6e 6b 20 6f 66 20 53 57 49 20 74 6f 20 63 6c |unk of SWI to cl|
000007b0 61 69 6d 2f 72 65 6c 65 61 73 65 0a 20 20 20 20 |aim/release. |
000007c0 20 20 20 20 20 20 20 20 7c 20 20 20 20 20 20 20 | | |
000007d0 20 20 62 69 74 73 20 36 2d 32 39 3a 20 75 6e 64 | bits 6-29: und|
000007e0 65 66 69 6e 65 64 2c 20 6c 65 61 76 65 20 75 6e |efined, leave un|
000007f0 73 65 74 0a 20 20 20 20 20 20 20 20 20 20 20 20 |set. |
00000800 7c 20 20 20 20 20 20 20 20 20 62 69 74 20 20 33 || bit 3|
00000810 30 20 20 3a 20 68 69 67 68 20 70 72 69 6f 72 69 |0 : high priori|
00000820 74 79 20 69 66 20 73 65 74 2c 20 65 6c 73 65 20 |ty if set, else |
00000830 6c 6f 77 20 70 72 69 6f 72 69 74 79 0a 20 20 20 |low priority. |
00000840 20 20 20 20 20 20 20 20 20 7c 20 20 20 20 20 20 | | |
00000850 20 20 20 62 69 74 20 20 33 31 20 20 3a 20 63 6c | bit 31 : cl|
00000860 61 69 6d 20 69 66 20 73 65 74 2c 20 65 6c 73 65 |aim if set, else|
00000870 20 72 65 6c 65 61 73 65 0a 20 20 20 20 20 20 20 | release. |
00000880 20 20 20 20 20 7c 20 52 32 20 3d 20 76 61 6c 75 | | R2 = valu|
00000890 65 20 74 6f 20 62 65 20 70 61 73 73 65 64 20 69 |e to be passed i|
000008a0 6e 20 52 31 32 20 6f 6e 20 65 6e 74 72 79 20 74 |n R12 on entry t|
000008b0 6f 20 63 6f 64 65 0a 20 20 20 20 20 20 20 20 20 |o code. |
000008c0 20 20 20 7c 20 52 33 20 3d 20 61 64 64 72 65 73 | | R3 = addres|
000008d0 73 20 6f 66 20 53 57 49 20 70 72 65 2d 74 72 61 |s of SWI pre-tra|
000008e0 70 70 69 6e 67 20 63 6f 64 65 2c 20 6f 72 20 30 |pping code, or 0|
000008f0 20 69 66 20 6e 6f 6e 65 20 6e 65 65 64 65 64 0a | if none needed.|
00000900 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 52 34 | | R4|
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000013a0 20 20 20 20 20 20 20 20 20 7c 20 50 6f 73 74 2d | | Post-|
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00001730 20 20 7c 20 52 65 6d 65 6d 62 65 72 20 74 68 61 | | Remember tha|
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00001990 20 43 6c 61 69 6d 69 6e 67 20 74 68 65 20 57 69 | Claiming the Wi|
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00001a00 63 69 72 63 75 6d 73 74 61 6e 63 65 73 20 73 68 |circumstances sh|
00001a10 6f 75 6c 64 20 79 6f 75 0a 20 20 20 20 20 20 20 |ould you. |
00001a20 20 20 20 20 20 7c 20 63 61 6c 6c 20 57 69 6d 70 | | call Wimp|
00001a30 5f 52 65 67 69 73 74 65 72 46 69 6c 74 65 72 20 |_RegisterFilter |
00001a40 77 69 74 68 20 57 69 6d 70 53 57 49 56 65 20 75 |with WimpSWIVe u|
00001a50 73 61 67 65 20 69 6e 20 79 6f 75 72 20 74 72 61 |sage in your tra|
00001a60 70 70 69 6e 67 0a 20 20 20 20 20 20 20 20 20 20 |pping. |
00001a70 20 20 7c 20 63 6f 64 65 2e 20 49 66 20 79 6f 75 | | code. If you|
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00001a90 69 6d 20 6f 72 20 72 65 6c 65 61 73 65 20 61 20 |im or release a |
00001aa0 53 57 49 20 77 68 65 6e 20 73 6f 6d 65 20 6f 74 |SWI when some ot|
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00001ac0 7c 20 53 57 49 20 69 73 20 65 78 65 63 75 74 65 || SWI is execute|
00001ad0 64 2c 20 75 73 65 20 61 20 43 61 6c 6c 42 61 63 |d, use a CallBac|
00001ae0 6b 20 74 6f 20 64 6f 20 69 74 2e 20 28 53 65 65 |k to do it. (See|
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00001b00 20 20 20 20 20 20 20 20 20 20 20 7c 20 50 72 6f | | Pro|
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00001b20 6e 63 65 20 4d 61 6e 75 61 6c 2c 20 70 61 67 65 |nce Manual, page|
00001b30 20 31 2d 33 31 39 2e 29 0a 20 20 20 20 20 20 20 | 1-319.). |
00001b40 20 20 20 20 20 7c 0a 20 20 20 20 20 20 20 20 20 | |. |
00001b50 20 20 20 7c 20 4e 42 3a 20 59 6f 75 20 73 68 6f | | NB: You sho|
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00001b90 20 20 20 20 20 20 20 20 20 20 20 7c 20 28 4f 72 | | (Or|
00001ba0 20 57 69 6d 70 5f 50 6f 6c 6c 49 64 6c 65 2e 29 | Wimp_PollIdle.)|
00001bb0 20 54 72 61 70 70 69 6e 67 20 57 69 6d 70 5f 50 | Trapping Wimp_P|
00001bc0 6f 6c 6c 20 69 73 20 65 61 73 79 20 61 6e 79 77 |oll is easy anyw|
00001bd0 61 79 2c 20 75 73 69 6e 67 0a 20 20 20 20 20 20 |ay, using. |
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00001c00 20 20 20 20 20 20 20 20 20 20 20 7c 0a 20 20 20 | |. |
00001c10 20 45 72 72 6f 72 73 3a 20 7c 20 42 61 64 20 76 | Errors: | Bad v|
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00001c30 49 4d 50 20 69 6e 20 52 30 0a 20 20 20 20 20 20 |IMP in R0. |
00001c40 20 20 20 20 20 20 7c 20 20 20 20 69 66 20 57 69 | | if Wi|
00001c50 6d 70 53 57 49 56 65 20 69 73 20 6e 6f 74 20 6c |mpSWIVe is not l|
00001c60 6f 61 64 65 64 2c 20 74 68 65 20 61 74 74 65 6d |oaded, the attem|
00001c70 70 74 20 74 6f 20 75 73 65 20 74 68 69 73 20 53 |pt to use this S|
00001c80 57 49 20 69 6e 0a 20 20 20 20 20 20 20 20 20 20 |WI in. |
00001c90 20 20 7c 20 20 20 20 74 68 65 20 57 69 6d 70 53 | | the WimpS|
00001ca0 57 49 56 65 20 6d 61 6e 6e 65 72 20 77 69 6c 6c |WIVe manner will|
00001cb0 20 63 61 75 73 65 20 74 68 69 73 20 65 72 72 6f | cause this erro|
00001cc0 72 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 |r. | |
00001cd0 42 61 64 20 57 69 6d 70 53 57 49 56 65 20 72 65 |Bad WimpSWIVe re|
00001ce0 6c 65 61 73 65 0a 20 20 20 20 20 20 20 20 20 20 |lease. |
00001cf0 20 20 7c 20 20 20 20 72 65 6c 65 61 73 69 6e 67 | | releasing|
00001d00 20 61 20 53 57 49 20 79 6f 75 20 68 61 64 20 6e | a SWI you had n|
00001d10 6f 74 20 63 6c 61 69 6d 65 64 20 67 65 6e 65 72 |ot claimed gener|
00001d20 61 74 65 73 20 74 68 69 73 20 65 72 72 6f 72 0a |ates this error.|
00001d30 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 4e 6f | | No|
00001d40 20 72 6f 6f 6d 20 69 6e 20 52 4d 41 0a 20 20 20 | room in RMA. |
00001d50 20 20 20 20 20 20 20 20 20 7c 20 20 20 20 69 73 | | is|
00001d60 20 61 6c 73 6f 20 70 6f 73 73 69 62 6c 65 20 62 | also possible b|
00001d70 75 74 20 68 69 67 68 6c 79 20 75 6e 6c 69 6b 65 |ut highly unlike|
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00001d90 7c 0a 0a 0a 20 46 6f 6f 74 6e 6f 74 65 20 31 20 ||... Footnote 1 |
00001da0 2d 20 52 65 2d 65 6e 74 72 61 6e 63 79 20 69 73 |- Re-entrancy is|
00001db0 73 75 65 73 3a 0a 0a 20 52 65 2d 65 6e 74 72 61 |sues:.. Re-entra|
00001dc0 6e 63 79 20 69 73 20 6e 61 65 20 70 72 6f 62 6c |ncy is nae probl|
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00001de0 73 65 20 70 72 65 2d 74 72 61 70 70 69 6e 67 20 |se pre-trapping |
00001df0 6f 72 20 6f 6e 6c 79 20 75 73 65 20 70 6f 73 74 |or only use post|
00001e00 2d 0a 74 72 61 70 70 69 6e 67 20 2d 20 79 6f 75 |-.trapping - you|
00001e10 20 63 61 6e 20 65 69 74 68 65 72 20 62 65 20 72 | can either be r|
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00001e30 6e 67 20 61 20 73 74 61 63 6b 20 74 6f 20 73 74 |ng a stack to st|
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00001e50 65 76 65 6e 74 20 72 65 2d 65 6e 74 65 72 69 6e |event re-enterin|
00001e60 67 20 75 73 69 6e 67 20 61 20 74 68 72 65 61 64 |g using a thread|
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00001e90 57 49 2c 20 79 6f 75 0a 63 61 6e 6e 6f 74 20 62 |WI, you.cannot b|
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00001ec0 20 62 6f 74 68 2c 20 62 75 74 20 74 68 65 20 70 | both, but the p|
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00001f80 66 6f 72 20 65 78 61 6d 70 6c 65 20 69 66 20 79 |for example if y|
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00002180 57 69 6d 70 5f 47 75 62 62 69 6e 73 20 63 61 75 |Wimp_Gubbins cau|
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000021b0 20 20 20 20 20 20 20 20 20 57 69 6d 70 53 57 49 | WimpSWI|
000021c0 56 65 20 63 6c 61 69 6d 61 6e 74 20 31 20 70 72 |Ve claimant 1 pr|
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000022c0 20 20 20 20 20 57 69 6d 70 53 57 49 56 65 20 63 | WimpSWIVe c|
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000025e0 20 54 68 65 72 65 20 61 72 65 20 74 77 6f 20 74 | There are two t|
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00002a60 6f 20 72 65 63 75 72 73 69 76 65 20 70 72 6f 62 |o recursive prob|
00002a70 6c 65 6d 73 0a 28 57 69 6d 70 5f 54 68 69 6e 67 |lems.(Wimp_Thing|
00002a80 20 63 61 6c 6c 73 20 57 69 6d 70 5f 47 75 62 62 | calls Wimp_Gubb|
00002a90 69 6e 73 20 63 61 6c 6c 73 20 57 69 6d 70 5f 54 |ins calls Wimp_T|
00002aa0 68 69 6e 67 20 63 61 6c 6c 73 20 57 69 6d 70 5f |hing calls Wimp_|
00002ab0 47 75 62 62 69 6e 73 20 65 74 63 2e 29 20 74 6f |Gubbins etc.) to|
00002ac0 6f 2e 0a 0a 20 53 6f 72 72 79 20 61 62 6f 75 74 |o... Sorry about|
00002ad0 20 74 68 65 20 63 6f 6d 70 6c 65 78 69 74 79 20 | the complexity |
00002ae0 6f 66 20 74 68 69 73 20 66 6f 6f 74 6e 6f 74 65 |of this footnote|
00002af0 2e 20 52 65 6c 61 78 2e 20 59 6f 75 20 64 6f 6e |. Relax. You don|
00002b00 27 74 20 6e 65 65 64 20 74 6f 0a 62 6f 74 68 65 |'t need to.bothe|
00002b10 72 20 61 62 6f 75 74 20 61 6c 6c 20 74 68 69 73 |r about all this|
00002b20 20 68 6f 72 72 69 64 20 73 74 75 66 66 2c 20 75 | horrid stuff, u|
00002b30 73 75 61 6c 6c 79 2e 20 3a 2d 29 0a 0a 0a 20 46 |sually. :-)... F|
00002b40 6f 6f 74 6e 6f 74 65 20 32 3a 0a 0a 20 59 6f 75 |ootnote 2:.. You|
00002b50 72 20 70 6f 73 74 2d 74 72 61 70 20 63 6f 64 65 |r post-trap code|
00002b60 20 77 69 6c 6c 20 6f 6e 6c 79 20 62 65 20 63 61 | will only be ca|
00002b70 6c 6c 65 64 20 69 66 20 74 68 65 20 53 57 49 20 |lled if the SWI |
00002b80 64 6f 65 73 20 72 65 74 75 72 6e 2e 20 54 68 69 |does return. Thi|
00002b90 73 20 6d 69 67 68 74 0a 6e 6f 74 20 68 61 70 70 |s might.not happ|
00002ba0 65 6e 20 69 66 20 74 68 65 20 53 57 49 20 69 73 |en if the SWI is|
00002bb0 20 6f 6e 65 20 74 68 61 74 20 64 6f 65 73 6e 27 | one that doesn'|
00002bc0 74 20 72 65 74 75 72 6e 20 28 62 75 74 20 49 20 |t return (but I |
00002bd0 63 61 6e 27 74 20 74 68 69 6e 6b 20 6f 66 20 61 |can't think of a|
00002be0 6e 79 0a 57 69 6d 70 5f 20 53 57 49 73 20 74 68 |ny.Wimp_ SWIs th|
00002bf0 61 74 20 64 6f 6e 27 74 29 2c 20 6f 72 20 69 66 |at don't), or if|
00002c00 20 61 20 73 65 72 69 6f 75 73 20 65 72 72 6f 72 | a serious error|
00002c10 20 68 61 70 70 65 6e 73 2e 20 54 68 65 20 6c 61 | happens. The la|
00002c20 74 74 65 72 20 73 68 6f 75 6c 64 0a 6e 65 76 65 |tter should.neve|
00002c30 72 20 68 61 70 70 65 6e 20 69 6e 20 61 20 70 65 |r happen in a pe|
00002c40 72 66 65 63 74 20 73 79 73 74 65 6d 2c 20 62 75 |rfect system, bu|
00002c50 74 20 62 75 67 73 20 68 61 70 70 65 6e 20 61 6e |t bugs happen an|
00002c60 64 20 74 68 65 20 53 57 49 20 62 65 69 6e 67 20 |d the SWI being |
00002c70 74 72 61 70 70 65 64 0a 6d 69 67 68 74 20 62 72 |trapped.might br|
00002c80 61 6e 63 68 20 74 68 72 6f 75 67 68 20 7a 65 72 |anch through zer|
00002c90 6f 20 6f 72 20 73 6f 6d 65 74 68 69 6e 67 2e 20 |o or something. |
00002ca0 57 69 74 68 20 74 68 65 20 57 69 6d 70 2c 20 74 |With the Wimp, t|
00002cb0 68 6f 75 67 68 2c 20 61 20 63 72 61 73 68 20 61 |hough, a crash a|
00002cc0 74 0a 74 68 69 73 20 73 74 61 67 65 20 6f 66 74 |t.this stage oft|
00002cd0 65 6e 20 6d 65 61 6e 73 20 74 68 65 72 65 20 69 |en means there i|
00002ce0 73 20 73 6f 6d 65 74 68 69 6e 67 20 76 65 72 79 |s something very|
00002cf0 20 77 72 6f 6e 67 20 77 69 74 68 20 74 68 65 20 | wrong with the |
00002d00 77 68 6f 6c 65 20 64 65 73 6b 74 6f 70 0a 61 6e |whole desktop.an|
00002d10 64 20 65 76 65 72 79 74 68 69 6e 67 20 69 73 20 |d everything is |
00002d20 67 6f 69 6e 67 20 74 6f 20 64 69 65 20 61 6e 79 |going to die any|
00002d30 77 61 79 2c 20 73 6f 20 79 6f 75 72 20 6d 6f 64 |way, so your mod|
00002d40 75 6c 65 20 66 61 69 6c 69 6e 67 20 74 6f 20 70 |ule failing to p|
00002d50 6f 73 74 2d 74 72 61 70 0a 69 73 20 75 6e 6c 69 |ost-trap.is unli|
00002d60 6b 65 6c 79 20 74 6f 20 61 6e 6e 6f 79 20 74 68 |kely to annoy th|
00002d70 65 20 75 73 65 72 20 6d 75 63 68 2e 20 3a 2d 29 |e user much. :-)|
00002d80 0a 0a 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |..--------------|
00002d90 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------|
*
00002dc0 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 0a |---------------.|
00002dd0 0a 20 54 68 69 73 20 6d 6f 64 75 6c 65 20 69 73 |. This module is|
00002de0 20 73 75 70 70 6c 69 65 64 20 77 69 74 68 20 73 | supplied with s|
00002df0 6f 6d 65 20 65 78 61 6d 70 6c 65 20 70 72 6f 67 |ome example prog|
00002e00 72 61 6d 73 3a 0a 0a 20 2d 20 33 44 45 72 72 6f |rams:.. - 3DErro|
00002e10 72 57 69 6e 64 6f 77 2e 20 54 68 69 73 20 69 73 |rWindow. This is|
00002e20 20 61 20 75 73 65 66 75 6c 20 6d 6f 64 75 6c 65 | a useful module|
00002e30 20 74 68 61 74 20 72 65 70 6c 61 63 65 73 20 74 | that replaces t|
00002e40 68 65 20 57 49 4d 50 91 73 20 65 72 72 6f 72 0a |he WIMP.s error.|
00002e50 20 20 20 77 69 6e 64 6f 77 73 20 77 69 74 68 20 | windows with |
00002e60 69 74 73 20 6f 77 6e 20 52 69 73 63 20 50 43 61 |its own Risc PCa|
00002e70 62 6c 65 20 33 44 20 6f 6e 65 73 20 28 69 74 20 |ble 3D ones (it |
00002e80 6e 65 65 64 73 20 33 44 45 72 72 6f 72 57 69 6e |needs 3DErrorWin|
00002e90 64 6f 77 24 50 61 74 68 20 74 6f 0a 20 20 20 70 |dow$Path to. p|
00002ea0 6f 69 6e 74 20 74 6f 20 61 20 64 69 72 65 63 74 |oint to a direct|
00002eb0 6f 72 79 20 63 6f 6e 74 61 69 6e 69 6e 67 20 54 |ory containing T|
00002ec0 65 6d 70 6c 61 74 65 73 20 61 6e 64 20 4d 65 73 |emplates and Mes|
00002ed0 73 61 67 65 73 20 2d 20 79 6f 75 20 63 61 6e 20 |sages - you can |
00002ee0 66 69 6e 64 20 6f 6e 65 0a 20 20 20 69 6e 20 53 |find one. in S|
00002ef0 6f 75 72 63 65 73 2e 45 72 72 6f 72 57 69 6e 64 |ources.ErrorWind|
00002f00 29 20 75 73 69 6e 67 20 70 72 65 2d 74 72 61 70 |) using pre-trap|
00002f10 70 69 6e 67 20 28 75 73 75 61 6c 6c 79 20 77 69 |ping (usually wi|
00002f20 74 68 20 69 6e 74 65 72 63 65 70 74 69 6f 6e 29 |th interception)|
00002f30 2e 20 54 68 65 0a 20 20 20 77 69 6e 64 6f 77 73 |. The. windows|
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00002f60 74 6c 65 6a 6f 69 6e 74 27 20 73 70 72 69 74 65 |tlejoint' sprite|
00002f70 20 69 6e 20 74 68 65 20 77 69 6d 70 20 70 6f 6f | in the wimp poo|
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00002fa0 6f 72 20 73 79 73 74 65 6d 20 73 70 72 69 74 65 |or system sprite|
00002fb0 73 2e 0a 20 2d 20 45 69 67 65 6e 53 79 73 49 6e |s.. - EigenSysIn|
00002fc0 66 6f 2e 20 54 68 69 73 20 69 73 20 61 20 70 72 |fo. This is a pr|
00002fd0 65 74 74 79 20 75 73 65 6c 65 73 73 20 6f 6e 65 |etty useless one|
00002fe0 20 74 68 61 74 20 63 68 61 6e 67 65 73 20 57 69 | that changes Wi|
00002ff0 6d 70 5f 52 65 61 64 53 79 73 49 6e 66 6f 0a 20 |mp_ReadSysInfo. |
00003000 20 20 32 20 61 6c 77 61 79 73 20 74 6f 20 72 65 | 2 always to re|
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00003030 74 74 65 72 20 69 66 20 4c 6f 67 32 59 45 69 67 |tter if Log2YEig|
00003040 3c 32 20 28 74 68 65 0a 20 20 20 57 49 4d 50 20 |<2 (the. WIMP |
00003050 72 65 74 75 72 6e 73 20 32 32 20 69 66 20 4c 6f |returns 22 if Lo|
00003060 67 32 59 45 69 67 3d 3d 4c 6f 67 32 58 45 69 67 |g2YEig==Log2XEig|
00003070 2c 20 77 68 69 63 68 20 69 73 20 73 69 6c 6c 79 |, which is silly|
00003080 29 2e 20 49 74 20 61 6c 73 6f 20 67 6f 65 73 0a |). It also goes.|
00003090 20 20 20 27 62 65 65 70 27 20 69 66 20 74 68 65 | 'beep' if the|
000030a0 20 57 69 6d 70 20 72 65 74 75 72 6e 65 64 20 61 | Wimp returned a|
000030b0 20 64 69 66 66 65 72 65 6e 74 20 76 61 6c 75 65 | different value|
000030c0 20 74 6f 20 69 74 20 28 74 72 79 20 6d 6f 64 65 | to it (try mode|
000030d0 20 32 32 20 61 6e 64 20 74 68 65 0a 20 20 20 6c | 22 and the. l|
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000030f0 61 72 74 69 63 75 6c 61 72 6c 79 20 67 72 65 61 |articularly grea|
00003100 74 20 62 65 63 61 75 73 65 20 6d 6f 73 74 20 70 |t because most p|
00003110 72 6f 67 72 61 6d 73 20 64 6f 6e 91 74 20 74 61 |rograms don.t ta|
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00003130 20 6f 66 20 52 65 61 64 53 79 73 49 6e 66 6f 20 | of ReadSysInfo |
00003140 28 70 61 72 74 6c 79 20 62 65 63 61 75 73 65 20 |(partly because |
00003150 6f 66 20 69 74 73 20 61 66 6f 72 65 6d 65 6e 74 |of its aforement|
00003160 69 6f 6e 65 64 20 62 6f 62 62 69 6e 73 6e 65 73 |ioned bobbinsnes|
00003170 73 29 0a 20 20 20 62 75 74 20 69 74 20 73 68 6f |s). but it sho|
00003180 77 73 20 79 6f 75 20 68 6f 77 20 74 6f 20 70 72 |ws you how to pr|
00003190 65 2d 74 72 61 70 20 61 6e 64 20 70 6f 73 74 2d |e-trap and post-|
000031a0 74 72 61 70 20 53 57 49 73 20 61 74 20 74 68 65 |trap SWIs at the|
000031b0 20 73 61 6d 65 20 74 69 6d 65 20 28 61 73 0a 20 | same time (as. |
000031c0 20 20 69 6e 20 66 6f 6f 74 6e 6f 74 65 20 31 29 | in footnote 1)|
000031d0 2e 0a 0a 20 54 68 65 20 73 6f 75 72 63 65 20 66 |... The source f|
000031e0 6f 72 20 74 68 65 73 65 20 70 72 6f 67 72 61 6d |or these program|
000031f0 73 2c 20 61 6c 6f 6e 67 20 77 69 74 68 20 74 68 |s, along with th|
00003200 65 20 66 75 6c 6c 20 73 6f 75 72 63 65 20 74 6f |e full source to|
00003210 20 57 69 6d 70 53 57 49 56 65 20 61 6e 64 0a 73 | WimpSWIVe and.s|
00003220 6f 6d 65 20 72 65 73 6f 75 72 63 65 73 20 66 6f |ome resources fo|
00003230 72 20 33 44 45 72 72 6f 72 57 69 6e 64 6f 77 20 |r 3DErrorWindow |
00003240 61 72 65 20 74 6f 20 62 65 20 66 6f 75 6e 64 20 |are to be found |
00003250 69 6e 20 74 68 65 20 53 6f 75 72 63 65 73 20 64 |in the Sources d|
00003260 69 72 65 63 74 6f 72 79 2e 0a 48 6f 77 65 76 65 |irectory..Howeve|
00003270 72 2c 20 74 68 65 73 65 20 70 72 6f 67 72 61 6d |r, these program|
00003280 73 20 72 65 71 75 69 72 65 20 42 41 58 20 74 6f |s require BAX to|
00003290 20 62 65 20 6c 6f 61 64 65 64 20 66 6f 72 20 74 | be loaded for t|
000032a0 68 65 6d 20 74 6f 20 63 6f 6d 70 69 6c 65 2e 20 |hem to compile. |
000032b0 42 41 58 20 69 73 0a 44 6f 67 67 79 53 6f 66 74 |BAX is.DoggySoft|
000032c0 91 73 20 42 61 73 69 63 20 41 73 73 65 6d 62 6c |.s Basic Assembl|
000032d0 65 72 20 45 78 74 65 6e 73 69 6f 6e 2c 20 77 68 |er Extension, wh|
000032e0 69 63 68 20 70 72 6f 76 69 64 65 73 20 61 6c 6c |ich provides all|
000032f0 20 41 52 4d 33 2c 20 41 52 4d 36 2c 20 46 50 41 | ARM3, ARM6, FPA|
00003300 31 30 0a 61 6e 64 20 63 6f 70 72 6f 63 65 73 73 |10.and coprocess|
00003310 6f 72 20 69 6e 73 74 72 75 63 74 69 6f 6e 73 2c |or instructions,|
00003320 20 61 6c 6f 6e 67 20 77 69 74 68 20 6d 61 6e 79 | along with many|
00003330 20 75 73 65 66 75 6c 20 70 73 65 75 64 6f 2d 69 | useful pseudo-i|
00003340 6e 73 74 72 75 63 74 69 6f 6e 73 2e 0a 59 6f 75 |nstructions..You|
00003350 20 63 61 6e 20 67 65 74 20 42 41 58 20 66 72 6f | can get BAX fro|
00003360 6d 20 67 6f 6f 64 20 50 44 20 6c 69 62 72 61 72 |m good PD librar|
00003370 69 65 73 20 61 6e 64 20 41 72 63 61 64 65 2c 20 |ies and Arcade, |
00003380 44 69 67 69 74 61 6c 20 44 61 74 61 62 61 6e 6b |Digital Databank|
00003390 20 61 6e 64 0a 46 75 72 7a 65 66 69 65 6c 64 20 | and.Furzefield |
000033a0 48 71 20 42 42 53 73 2e 20 49 74 91 73 20 65 73 |Hq BBSs. It.s es|
000033b0 73 65 6e 74 69 61 6c 20 66 6f 72 20 42 61 73 69 |sential for Basi|
000033c0 63 20 61 73 73 65 6d 62 6c 65 72 20 70 72 6f 67 |c assembler prog|
000033d0 72 61 6d 6d 65 72 73 21 0a 0a 20 49 66 20 79 6f |rammers!.. If yo|
000033e0 75 20 75 73 65 20 74 68 69 73 20 6d 6f 64 75 6c |u use this modul|
000033f0 65 20 69 6e 20 61 20 70 72 6f 67 72 61 6d 2c 20 |e in a program, |
00003400 62 65 20 73 75 72 65 20 74 6f 20 52 4d 45 6e 73 |be sure to RMEns|
00003410 75 72 65 20 76 65 72 73 69 6f 6e 20 30 2e 30 34 |ure version 0.04|
00003420 20 6f 72 0a 6c 61 74 65 72 20 2d 20 76 65 72 73 | or.later - vers|
00003430 69 6f 6e 73 20 30 2e 30 31 20 61 6e 64 20 30 2e |ions 0.01 and 0.|
00003440 30 32 20 61 72 65 20 4e 65 77 65 72 4c 6f 6f 6b |02 are NewerLook|
00003450 20 71 75 69 63 6b 20 72 65 6c 65 61 73 65 73 20 | quick releases |
00003460 77 69 74 68 20 62 75 67 73 20 69 6e 0a 70 6f 73 |with bugs in.pos|
00003470 74 2d 74 72 61 70 70 69 6e 67 2c 20 61 6e 64 20 |t-trapping, and |
00003480 76 65 72 73 69 6f 6e 20 30 2e 30 33 20 64 6f 20 |version 0.03 do |
00003490 6e 6f 74 20 66 65 61 74 75 72 65 20 68 69 67 68 |not feature high|
000034a0 2d 70 72 69 6f 72 69 74 79 20 53 57 49 20 74 72 |-priority SWI tr|
000034b0 61 70 70 69 6e 67 2c 0a 61 73 20 77 65 6c 6c 20 |apping,.as well |
000034c0 61 73 20 73 6f 6d 65 74 69 6d 65 73 20 65 6e 74 |as sometimes ent|
000034d0 65 72 69 6e 67 20 70 72 65 2d 63 6f 64 65 20 77 |ering pre-code w|
000034e0 69 74 68 20 69 6e 74 65 72 72 75 70 74 73 20 65 |ith interrupts e|
000034f0 6e 61 62 6c 65 64 2e 0a 0a 20 54 68 69 73 20 6d |nabled... This m|
00003500 6f 64 75 6c 65 20 69 73 20 66 72 65 65 77 61 72 |odule is freewar|
00003510 65 2e 20 46 72 65 65 20 66 72 65 65 20 74 6f 20 |e. Free free to |
00003520 64 69 73 74 72 69 62 75 74 65 20 61 6e 64 20 75 |distribute and u|
00003530 73 65 2e 20 54 6f 20 63 6f 6e 74 61 63 74 20 6d |se. To contact m|
00003540 65 20 2d 0a 66 6f 72 20 70 72 61 69 73 65 2c 20 |e -.for praise, |
00003550 74 6f 20 73 75 67 67 65 73 74 20 6e 65 77 20 62 |to suggest new b|
00003560 69 74 73 20 74 6f 20 61 64 64 2c 20 6f 72 20 28 |its to add, or (|
00003570 68 65 61 76 65 6e 20 66 6f 72 62 69 64 29 20 74 |heaven forbid) t|
00003580 6f 20 72 65 70 6f 72 74 20 61 20 62 75 67 2c 0a |o report a bug,.|
00003590 70 6c 65 61 73 65 20 77 72 69 74 65 20 74 6f 3a |please write to:|
000035a0 0a 0a 20 20 41 6e 64 72 65 77 20 43 6c 6f 76 65 |.. Andrew Clove|
000035b0 72 2c 0a 20 20 20 37 20 42 6c 61 63 6b 68 6f 72 |r,. 7 Blackhor|
000035c0 73 65 20 43 72 65 73 63 65 6e 74 2c 0a 20 20 20 |se Crescent,. |
000035d0 20 41 6d 65 72 73 68 61 6d 2c 0a 20 20 20 20 20 | Amersham,. |
000035e0 42 75 63 6b 73 2e 2c 0a 20 20 20 20 20 20 48 50 |Bucks.,. HP|
000035f0 36 20 36 48 50 2e 0a 0a 20 4f 72 20 70 68 6f 6e |6 6HP... Or phon|
00003600 65 20 6d 65 20 6f 6e 20 30 31 34 39 34 2d 34 33 |e me on 01494-43|
00003610 31 39 31 36 2c 20 73 65 6e 64 20 61 20 66 61 78 |1916, send a fax|
00003620 20 6f 6e 20 30 31 34 39 34 2d 36 37 35 38 37 38 | on 01494-675878|
00003630 2c 20 73 65 6e 64 20 73 6f 6d 65 20 65 6d 61 69 |, send some emai|
00003640 6c 20 74 6f 0a 61 6a 63 40 64 6f 67 67 79 73 66 |l to.ajc@doggysf|
00003650 74 2e 64 65 6d 6f 6e 2e 63 6f 2e 75 6b 20 6f 72 |t.demon.co.uk or|
00003660 20 65 76 65 6e 20 74 65 6c 65 78 20 6f 6e 20 38 | even telex on 8|
00003670 33 36 37 35 20 42 72 69 74 20 47 2e 0a |3675 Brit G..|
0000367d 
.