general commands, same for flash card or NON flash card,
I don't know what they do exactly.

c1 00 00 00 21 05 01 00

c1 00 00 00 20 05 01 00		This one appeares only right after issuing any delete command
				41 0a 01 00 0d 00 00 00 (for pic 01). It appears after every
				 delete comand. I dont't know what
				it does. The camera answers as usual with a "00" Byte.

41 02 00 00 07 00 00 00		This appears after the
				41 0a 0x 00 0d 00 00 00
				c1 00 00 00 20 05 01 00
				sequence.
				It also appears before these two basic commands:
				41 0a 00 00 00 00 00 00
				41 0a 00 00 01 00 00 00

41 0a 00 00 00 00 00 00		This I believe to be a reset command. It is issued in the very
				beginning and for example after dleting all the pictures, just
				before the directory is reread with the
				41 0a 00 00 01 00 00 00
				command.

c1 00 00 00 00 80 01 00		This appears before every 41 0a command. And usually after a
				c1 00 00 00 21 05 01 00. But not always.

c1 00 00 00 85 89 01 00		After a long transfer and after al the picture info transfers
				this is sent until something else happens.
				To me it looks like a "keepalive"
				Every other minute (?) this is interuppted by a combination
				of:
				c1 00 00 00 21 05 01 00
				c1 00 00 00 00 80 01 00
				c1 00 00 00 21 05 01 00
				c1 00 00 00 00 80 01 00
				Then it continues.

	UPDATE: dennis 09.09.02
	The command "c1 00 00 00 85 89 01 00" is a polling command to query the status of the
	"print" button on the camera. It appears whenever nothing else is happening, and is
	needed to catch the user pressing the print button. Keepalive is not necessary with
	USB.



Using a compact flash card:

41 0a 00 00 01 00 00 00		Send the basic directory info

41 0a 03 00 08 00 00 00 	send infos for picture number 03

41 0a 03 00 00 0a 00 00		Send picture number 03

41 0a 03 00 00 0d 00 00		Delete picture number 03


WITHOUT a compact flash card:

41 0a 00 00 01 00 00 00         Send the basic directory info

41 03 ff 0f 00 00 00 00         send infos for the first picture
41 03 fe 0f 00 00 00 00		send infos for the second picture
41 03 fd 0f 00 00 00 00		guess what? :))

41 03 ff 0f 08 00 00 00		send the first picture
41 03 fe 0f 08 00 00 00		send the second picture
41 03 fd 0f 08 00 00 00		you know what...