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PCA/Docs/PCA_SWIs

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Filename: PCA/Docs/PCA_SWIs
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File contents
Plug In Compliant Application protocol
====================================== 


PCA support module SWIs
=======================

Module : PCASupport
Version : 0.07 (12 August 1996)
Chunk : &4D6C0

The PCA support module is designed to facilitate the creation of PCA style
'tags' in an area of shared memory. At a future date other useful PCA
related SWIs (eg. colaescing update area rectangles) may be added. In the
meantime the following SWIs are provided. 
  
SWI PCA_CreateTag
-----------------  
on entry -
 
r1 = address of base
r2 = Offset to object
r3 = size of object (optional)
r4 = flags/extension data (not in this version.)
 
on exit -
 
r0 = address of tag
(r1-r4 are written into the tag as initial values.)
All other registers preserved.
 
 
Errors returnable:
 
"This version of the PCA support module cannot create extended tags."

Produced if bits set in R4 (b0-15).
 
"This version does not resize the tag block on old hardware. (too many tags)."

Produced on pre-RPC hardware if more than 2048 tags are in use.
 
  
NOTE: PCASupport relies on the first value of a valid tag not being
&FFFFFFFF (-1). NEVER write this value into the base field of the tag as the
next call to PCA_CreateTag will probably map your tag to another object -
causing chaos. 
 
  
SWI PCA_DeleteTag
-----------------  
on entry -
 
R0 = ptr to tag
 
on exit all registers preserved.
 
Errors returnable:
"Bad tag passed to PCASupport."
 
  
SWI PCA_DeleteAndKill
---------------------  
on entry -
 
R0 = ptr to tag
R1 = filetype of object
 
on exit all registers preserved.
  
As well as the functionality of the above SWI this also broadcasts
Message_Deselect for you.
00000000  50 6c 75 67 20 49 6e 20  43 6f 6d 70 6c 69 61 6e  |Plug In Complian|
00000010  74 20 41 70 70 6c 69 63  61 74 69 6f 6e 20 70 72  |t Application pr|
00000020  6f 74 6f 63 6f 6c 0a 3d  3d 3d 3d 3d 3d 3d 3d 3d  |otocol.=========|
00000030  3d 3d 3d 3d 3d 3d 3d 3d  3d 3d 3d 3d 3d 3d 3d 3d  |================|
00000040  3d 3d 3d 3d 3d 3d 3d 3d  3d 3d 3d 3d 3d 20 0a 0a  |============= ..|
00000050  0a 50 43 41 20 73 75 70  70 6f 72 74 20 6d 6f 64  |.PCA support mod|
00000060  75 6c 65 20 53 57 49 73  0a 3d 3d 3d 3d 3d 3d 3d  |ule SWIs.=======|
00000070  3d 3d 3d 3d 3d 3d 3d 3d  3d 3d 3d 3d 3d 3d 3d 3d  |================|
00000080  0a 0a 4d 6f 64 75 6c 65  20 3a 20 50 43 41 53 75  |..Module : PCASu|
00000090  70 70 6f 72 74 0a 56 65  72 73 69 6f 6e 20 3a 20  |pport.Version : |
000000a0  30 2e 30 37 20 28 31 32  20 41 75 67 75 73 74 20  |0.07 (12 August |
000000b0  31 39 39 36 29 0a 43 68  75 6e 6b 20 3a 20 26 34  |1996).Chunk : &4|
000000c0  44 36 43 30 0a 0a 54 68  65 20 50 43 41 20 73 75  |D6C0..The PCA su|
000000d0  70 70 6f 72 74 20 6d 6f  64 75 6c 65 20 69 73 20  |pport module is |
000000e0  64 65 73 69 67 6e 65 64  20 74 6f 20 66 61 63 69  |designed to faci|
000000f0  6c 69 74 61 74 65 20 74  68 65 20 63 72 65 61 74  |litate the creat|
00000100  69 6f 6e 20 6f 66 20 50  43 41 20 73 74 79 6c 65  |ion of PCA style|
00000110  0a 27 74 61 67 73 27 20  69 6e 20 61 6e 20 61 72  |.'tags' in an ar|
00000120  65 61 20 6f 66 20 73 68  61 72 65 64 20 6d 65 6d  |ea of shared mem|
00000130  6f 72 79 2e 20 41 74 20  61 20 66 75 74 75 72 65  |ory. At a future|
00000140  20 64 61 74 65 20 6f 74  68 65 72 20 75 73 65 66  | date other usef|
00000150  75 6c 20 50 43 41 0a 72  65 6c 61 74 65 64 20 53  |ul PCA.related S|
00000160  57 49 73 20 28 65 67 2e  20 63 6f 6c 61 65 73 63  |WIs (eg. colaesc|
00000170  69 6e 67 20 75 70 64 61  74 65 20 61 72 65 61 20  |ing update area |
00000180  72 65 63 74 61 6e 67 6c  65 73 29 20 6d 61 79 20  |rectangles) may |
00000190  62 65 20 61 64 64 65 64  2e 20 49 6e 20 74 68 65  |be added. In the|
000001a0  0a 6d 65 61 6e 74 69 6d  65 20 74 68 65 20 66 6f  |.meantime the fo|
000001b0  6c 6c 6f 77 69 6e 67 20  53 57 49 73 20 61 72 65  |llowing SWIs are|
000001c0  20 70 72 6f 76 69 64 65  64 2e 20 0a 20 20 0a 53  | provided. .  .S|
000001d0  57 49 20 50 43 41 5f 43  72 65 61 74 65 54 61 67  |WI PCA_CreateTag|
000001e0  0a 2d 2d 2d 2d 2d 2d 2d  2d 2d 2d 2d 2d 2d 2d 2d  |.---------------|
000001f0  2d 2d 20 20 0a 6f 6e 20  65 6e 74 72 79 20 2d 0a  |--  .on entry -.|
00000200  20 0a 72 31 20 3d 20 61  64 64 72 65 73 73 20 6f  | .r1 = address o|
00000210  66 20 62 61 73 65 0a 72  32 20 3d 20 4f 66 66 73  |f base.r2 = Offs|
00000220  65 74 20 74 6f 20 6f 62  6a 65 63 74 0a 72 33 20  |et to object.r3 |
00000230  3d 20 73 69 7a 65 20 6f  66 20 6f 62 6a 65 63 74  |= size of object|
00000240  20 28 6f 70 74 69 6f 6e  61 6c 29 0a 72 34 20 3d  | (optional).r4 =|
00000250  20 66 6c 61 67 73 2f 65  78 74 65 6e 73 69 6f 6e  | flags/extension|
00000260  20 64 61 74 61 20 28 6e  6f 74 20 69 6e 20 74 68  | data (not in th|
00000270  69 73 20 76 65 72 73 69  6f 6e 2e 29 0a 20 0a 6f  |is version.). .o|
00000280  6e 20 65 78 69 74 20 2d  0a 20 0a 72 30 20 3d 20  |n exit -. .r0 = |
00000290  61 64 64 72 65 73 73 20  6f 66 20 74 61 67 0a 28  |address of tag.(|
000002a0  72 31 2d 72 34 20 61 72  65 20 77 72 69 74 74 65  |r1-r4 are writte|
000002b0  6e 20 69 6e 74 6f 20 74  68 65 20 74 61 67 20 61  |n into the tag a|
000002c0  73 20 69 6e 69 74 69 61  6c 20 76 61 6c 75 65 73  |s initial values|
000002d0  2e 29 0a 41 6c 6c 20 6f  74 68 65 72 20 72 65 67  |.).All other reg|
000002e0  69 73 74 65 72 73 20 70  72 65 73 65 72 76 65 64  |isters preserved|
000002f0  2e 0a 20 0a 20 0a 45 72  72 6f 72 73 20 72 65 74  |.. . .Errors ret|
00000300  75 72 6e 61 62 6c 65 3a  0a 20 0a 22 54 68 69 73  |urnable:. ."This|
00000310  20 76 65 72 73 69 6f 6e  20 6f 66 20 74 68 65 20  | version of the |
00000320  50 43 41 20 73 75 70 70  6f 72 74 20 6d 6f 64 75  |PCA support modu|
00000330  6c 65 20 63 61 6e 6e 6f  74 20 63 72 65 61 74 65  |le cannot create|
00000340  20 65 78 74 65 6e 64 65  64 20 74 61 67 73 2e 22  | extended tags."|
00000350  0a 0a 50 72 6f 64 75 63  65 64 20 69 66 20 62 69  |..Produced if bi|
00000360  74 73 20 73 65 74 20 69  6e 20 52 34 20 28 62 30  |ts set in R4 (b0|
00000370  2d 31 35 29 2e 0a 20 0a  22 54 68 69 73 20 76 65  |-15).. ."This ve|
00000380  72 73 69 6f 6e 20 64 6f  65 73 20 6e 6f 74 20 72  |rsion does not r|
00000390  65 73 69 7a 65 20 74 68  65 20 74 61 67 20 62 6c  |esize the tag bl|
000003a0  6f 63 6b 20 6f 6e 20 6f  6c 64 20 68 61 72 64 77  |ock on old hardw|
000003b0  61 72 65 2e 20 28 74 6f  6f 20 6d 61 6e 79 20 74  |are. (too many t|
000003c0  61 67 73 29 2e 22 0a 0a  50 72 6f 64 75 63 65 64  |ags)."..Produced|
000003d0  20 6f 6e 20 70 72 65 2d  52 50 43 20 68 61 72 64  | on pre-RPC hard|
000003e0  77 61 72 65 20 69 66 20  6d 6f 72 65 20 74 68 61  |ware if more tha|
000003f0  6e 20 32 30 34 38 20 74  61 67 73 20 61 72 65 20  |n 2048 tags are |
00000400  69 6e 20 75 73 65 2e 0a  20 0a 20 20 0a 4e 4f 54  |in use.. .  .NOT|
00000410  45 3a 20 50 43 41 53 75  70 70 6f 72 74 20 72 65  |E: PCASupport re|
00000420  6c 69 65 73 20 6f 6e 20  74 68 65 20 66 69 72 73  |lies on the firs|
00000430  74 20 76 61 6c 75 65 20  6f 66 20 61 20 76 61 6c  |t value of a val|
00000440  69 64 20 74 61 67 20 6e  6f 74 20 62 65 69 6e 67  |id tag not being|
00000450  0a 26 46 46 46 46 46 46  46 46 20 28 2d 31 29 2e  |.&FFFFFFFF (-1).|
00000460  20 4e 45 56 45 52 20 77  72 69 74 65 20 74 68 69  | NEVER write thi|
00000470  73 20 76 61 6c 75 65 20  69 6e 74 6f 20 74 68 65  |s value into the|
00000480  20 62 61 73 65 20 66 69  65 6c 64 20 6f 66 20 74  | base field of t|
00000490  68 65 20 74 61 67 20 61  73 20 74 68 65 0a 6e 65  |he tag as the.ne|
000004a0  78 74 20 63 61 6c 6c 20  74 6f 20 50 43 41 5f 43  |xt call to PCA_C|
000004b0  72 65 61 74 65 54 61 67  20 77 69 6c 6c 20 70 72  |reateTag will pr|
000004c0  6f 62 61 62 6c 79 20 6d  61 70 20 79 6f 75 72 20  |obably map your |
000004d0  74 61 67 20 74 6f 20 61  6e 6f 74 68 65 72 20 6f  |tag to another o|
000004e0  62 6a 65 63 74 20 2d 0a  63 61 75 73 69 6e 67 20  |bject -.causing |
000004f0  63 68 61 6f 73 2e 20 0a  20 0a 20 20 0a 53 57 49  |chaos. . .  .SWI|
00000500  20 50 43 41 5f 44 65 6c  65 74 65 54 61 67 0a 2d  | PCA_DeleteTag.-|
00000510  2d 2d 2d 2d 2d 2d 2d 2d  2d 2d 2d 2d 2d 2d 2d 2d  |----------------|
00000520  20 20 0a 6f 6e 20 65 6e  74 72 79 20 2d 0a 20 0a  |  .on entry -. .|
00000530  52 30 20 3d 20 70 74 72  20 74 6f 20 74 61 67 0a  |R0 = ptr to tag.|
00000540  20 0a 6f 6e 20 65 78 69  74 20 61 6c 6c 20 72 65  | .on exit all re|
00000550  67 69 73 74 65 72 73 20  70 72 65 73 65 72 76 65  |gisters preserve|
00000560  64 2e 0a 20 0a 45 72 72  6f 72 73 20 72 65 74 75  |d.. .Errors retu|
00000570  72 6e 61 62 6c 65 3a 0a  22 42 61 64 20 74 61 67  |rnable:."Bad tag|
00000580  20 70 61 73 73 65 64 20  74 6f 20 50 43 41 53 75  | passed to PCASu|
00000590  70 70 6f 72 74 2e 22 0a  20 0a 20 20 0a 53 57 49  |pport.". .  .SWI|
000005a0  20 50 43 41 5f 44 65 6c  65 74 65 41 6e 64 4b 69  | PCA_DeleteAndKi|
000005b0  6c 6c 0a 2d 2d 2d 2d 2d  2d 2d 2d 2d 2d 2d 2d 2d  |ll.-------------|
000005c0  2d 2d 2d 2d 2d 2d 2d 2d  20 20 0a 6f 6e 20 65 6e  |--------  .on en|
000005d0  74 72 79 20 2d 0a 20 0a  52 30 20 3d 20 70 74 72  |try -. .R0 = ptr|
000005e0  20 74 6f 20 74 61 67 0a  52 31 20 3d 20 66 69 6c  | to tag.R1 = fil|
000005f0  65 74 79 70 65 20 6f 66  20 6f 62 6a 65 63 74 0a  |etype of object.|
00000600  20 0a 6f 6e 20 65 78 69  74 20 61 6c 6c 20 72 65  | .on exit all re|
00000610  67 69 73 74 65 72 73 20  70 72 65 73 65 72 76 65  |gisters preserve|
00000620  64 2e 0a 20 20 0a 41 73  20 77 65 6c 6c 20 61 73  |d..  .As well as|
00000630  20 74 68 65 20 66 75 6e  63 74 69 6f 6e 61 6c 69  | the functionali|
00000640  74 79 20 6f 66 20 74 68  65 20 61 62 6f 76 65 20  |ty of the above |
00000650  53 57 49 20 74 68 69 73  20 61 6c 73 6f 20 62 72  |SWI this also br|
00000660  6f 61 64 63 61 73 74 73  0a 4d 65 73 73 61 67 65  |oadcasts.Message|
00000670  5f 44 65 73 65 6c 65 63  74 20 66 6f 72 20 79 6f  |_Deselect for yo|
00000680  75 2e                                             |u.|
00000682