README.epson, 16th April 1999, Clive Stubbings, www.vjet.demon.co.uk/scanner

Its all a bit rambling.... but its my best guess so far as to what the epson
FS200 commands do.. Though see the code too...



Commands: (reponses)
@ - reset			(no params)
A - set area		(8 bytes of params)
B - halftone - not for fs200
C - set mode		(1 byte of params) [0,2,3,18,19]
D - depth			(1 byte of params) [1,2,3,4,5,6,7,8]
G - scan			(no params)
H - zoom			(2 bytes of params) [50-200] [50-200] (xzoom, yzoom)
I - identify		(returns stuff)
K - orientation		(1 byte of params) [0,1,2,3] (1=l/r swap,2=inverted, 3=both)
L - brightness		(1 byte of params) ?[0,1,2,3,253,254,255]
M - colour			(1 byte of params) [0,1,16,32,64,128]
N - film type		(1 byte of params) [0,1,2,3]
P - Unknown			(1 byte of params) [0-196]
Q - sharpen			(1 byte of params) (+2 -> -2) [0,1,2,254,255]
R - resolution		(4 bytes of params) [0-xres, 0-yres]
T - Unknown			(1 byte of params) [0]
W - Unknown			(returns data)
Z - gamma			(1 byte of params) [0,1,2,3,16,32]
d - lcount			(1 byte of params) [0-255]
g - speed?			(1 byte of params) [0,1]
m - Unknown			(1 byte of params) [0-255]
z - Unknown			(1 byte of params) [66,71,77,82,98,103,109,114][BGMRbgmr]
_ - Unknown			(returns data)


W - returns 21,87,161,1 rather than ACK
_ - returns 2,100,32,3  and seems to perform an image scan. Using 32/3 as
	a buffer size + reading data didn't seem to do much.
	However - using it as a scan command just crashed everything.

M - colour

N - filmtype - 0 pos film, 1 neg film, 2 pos slide, 3 neg slide

P - all values tried cause scan start to fail...

Q - Sharpness -2 to +2

H - zoom 50-200%

T - seems to have no effect in colour neg-film or pos-slide

g - 1 high speed (low quality preview scan) 0 - fine (normal) scan

m - seems to have no effect in binary or colour modes

z - seems to have no effect in colour or grey modes



scan			\033G
		cancel scan	\030
		continue scan \006


	send:	\033G			start scan
	get:	6 bytes			(STX,flags,linelen*2,nlines*2)
	get:	buf_len bytes
	
	flags:	colour (0x08), EOF(0x20), ??(0x40),, Error (oc80)

	if flag && EOF
		done
	else
		send \006 to continue, \030 to abort

set mode:		\033C	mode(byte)
 * For the FS200 the only valid modes (8 bit depth) are:
 *	00000000	- 3 small monochrome images...
 *	00000010	- colour (need to NOT set lcount)
 *	00000011	- colour - red/green swapped?
 *	00010010	- colour - red/green swapped? (need to NOT set lcount)
 *	00010011	- colour

identify		\033I												[I]
	Returns a buffer full of info
		0:	type		\ used to identify device capabilities
		1:	level		/

		R xxxx 			- DPI options (3 bytes each)
						xxxx = buf[n+1] + 256*buf[n+2]

		A xxxx yyyy		- X and Y max range (in dots at max DPI)
			xxxx = buf[n+1] + 256*buf[n+2]
			in mm's = (xxxx * 25.4) / max_dpi