Just realized you're talking about firmware code snippets. Sorry.
Just an idea and it may not help much (based on observations on earlier models):
The 0xc022xxxx GPIO area holds two representations of the GPIO "pins". The first one uses a whole word (32bits) to set up (and read/write) a single "pin", the second one collects the states of multiple "pins" into a few words (1 bit / GPIO).
One can use the 32bit/pin representation to set up hardware properties of that pin (e.g. set it as input or output, set pullup/pulldown resistor, set driving mode, etc). That is the reason for using 0x46/0x44.
I think this still applies to the DIGIC 5 (since manipulating bits of a word without affecting all the other bits is not possible on ARM, and this is not a regular memory area). I think what you've found is the grouped version (1bit/pin).
edit:
I was curious and tried modifying the Canon Basic dumper script to dump the 0xc022.... area. It seemed to work ... on the A410 and the Ixus870.
' dump 0xC022xxxx to A/C022.BIN
' log to A/CBDUMPER.LOG
DIM startaddr=0xC0220000
DIM os="unk"
DIM lcdmsg=0
DIM msgstr=0
private sub RegisterProcs()
' Newest cams (Dryos rel 43 and later) only have System.Create()
' on older dryos cams SystemEventInit is an alias for System.Create()
' ExecuteEventProcedure does is not registered by default on vx,
' but calling an unregistered is not fatal
if System.Create() = -1 then
SystemEventInit()
end if
if ExecuteEventProcedure("UI_RegistDebugEventProc") = -1 then
ExecuteEventProcedure("UI.CreatePublic")
end if
end sub
private sub InitMsg()
lcdmsg = ExecuteEventProcedure("LCDMsg_Create")
msgstr = AllocateMemory(80)
' truncate log
msgfile = Fopen_Fut("A/CBDUMPER.LOG","w")
if msgfile <> 0 then
Fclose_Fut(msgfile)
end if
end sub
private sub PutMsg(msg)
if lcdmsg >= 0 then
LCDMsg_SetStr(lcdmsg,msg)
LCDMsg_ChangeColor(lcdmsg ,6)
end if
msgfile = Fopen_Fut("A/CBDUMPER.LOG","a")
if msgfile <> 0 then
Fwrite_Fut(msg,strlen(msg),1,msgfile)
Fwrite_Fut("\n",1,1,msgfile)
Fclose_Fut(msgfile)
end if
end sub
private sub Initialize()
RegisterProcs()
InitMsg()
PutMsg("Started")
if startaddr <> 0 then
sprintf(msgstr,"%0X %s",startaddr,os)
PutMsg(msgstr)
' romsize = 0xFFFFFFFC - startaddr
romsize = 0xFFFC
dumpfile = Fopen_Fut("A/C022.BIN","w")
if dumpfile <> 0 then
Fwrite_Fut(startaddr,romsize,1,dumpfile)
Fclose_Fut(dumpfile)
Wait(500)
PutMsg("done")
else
PutMsg("file error")
end if
else
PutMsg("not found!")
end if
FreeMemory(msgstr)
end sub
