#!/usr/bin/wish

##############################################################
#    Global flags and variables
##############################################################

# Flags
set waiting_for_key 0
set question_asked 0
set timer_started 0

# Channel to talk to the MRC device
set MRC 0

#  Mapping of MCR codes to keys:  button(code)
set buttoncode 256
for {set i 1} {$i <=8} {incr i} {
    set button($buttoncode) $i
    set buttoncode [expr $buttoncode*2]
}


##############################################################
#  Procedures for talking with MRC
##############################################################

# Open the given device for MRC.  Return 0 if successful, 1 otherwise
proc open_mrc {device} {
    global MRC
    set result [catch {set MRC [open $device r+]}]
    if {$result !=0} {
	return $result
    }
    fconfigure $MRC -blocking 0  -translation binary \
	-encoding binary -buffering none -mode  57600,n,8,1
    
    puts $MRC s
    after 200
    read $MRC
    puts $MRC r
    after 200
    read $MRC
    return 0
}
    


# Return the key pressed or 0
proc readbuffer {} {
    global MRC  button
    set key 0
    set message [read $MRC]
    binary scan $message s key
    set key [expr $key & 0xFFFF]
    if {[catch {set key $button($key)}] == 0} {
	return $key
    }
    return 0
}

##############################################################
#   Setup
##############################################################

button .start -text "Start" -command start
pack .start
label .pressed 
pack .pressed


proc start {} {
    global SRLFILE state idle waiting
    readbuffer
    .start configure -state disabled -command {}
    set state $waiting
}

proc body  {} {
    global state idle waiting
    update idletasks
    if { $state == $waiting } {
	set pressed [readbuffer]
	if { $pressed != 0 } {
#	    set state $idle
#	    .start configure -state active -command start
	    .pressed configure -text "Pressed $pressed"
	    puts $pressed
	    readbuffer	}
    } else {
	readbuffer
    }
    after 10 body
}

body