Commodore Amiga A500 Technical Reference Manual page 151

memrw.i-parameter area definition for access t o other
processors mem
Copyright 0 1986, Commodore-Amiga Inc.,
All
rights reserved
IFND JANUS-MEMRW-I
JANUS-MEMRW-I SET
1
;
this is the parameter block for the JSERV-READPC and JSERV-
;
READAMIGA; services
-
read andtor write the other processors
;
memory.
STRUCTURE MemReadWrite,O
UWORD mm-Command
;
see below for list of commands
UWORD m w C o u n t
;
number of bytes t o transfer
ULONG mnvAddress
;
local address to access. This is
;
a machine pointer for the 68000, and
;
a s e g m e n t l o ~ pair for the
808x.
;
The address is arranged so the native
;
processor may read it directly.
UWORD m ~ B u f f e r
;
The offset in buffer memory for the
;
other buffer.
UWORD mm-Status
;
See below for status.
LABEL MemReadWrite-SIZEOF
;
Command definitions:
MRWC-NOP
EQU
0
;
do nothing
-
return OK status
code
MRWC-READ EQU 1
;
xfer from address to buffer
MRWC-WRITE EQU 2
;
xfer from buffer to address
MRWC-READIO EQU
3
;
only on 808x
-
read from 1 0
space
MRWC-WRITE10 EQU
4
;
only on 808x
-
write t o
1 0
space
MRWC-WRITEREAD EQU 5
;
write from buffer, then read back
;
Status definitions:
MRWSINPRCGRESS EQU $ffff
;
we've noticed command and
are working on it
MRWS-OK EQU
$0000
;
completed OK
MRWSACCESSERR EQU $0001
;
some sort of protection
violation
MRWSBADCMD EQU $0002
;
command that the server
doesn't understand
ENDC
l
FND JANUSSERVlCESl
JANUSSERVICE5I EQU 1