[time-nuts] Serial Port Logging Script?

[Christian Vogel]

Hi everyone,

I have been lurking for quite some time, so let me use this
opportunity to say hello to everyone.

Regarding logging serial port-data to files, there is always
trusty old tcl. It should be installed on almost every Solaris,
HPUX, AIX, Linux, Freebsd, ... machine there is.

I used the "extended" version below to read out a Hameg-8123
counter over a period of several weeks, it worked flawlessly.

The "reduced" version will just print out all lines it receives,
prefixed with a human-readable and a unix-since-epoch timestamp.

21:15:35 1166818535 FRA 9.999984604 MHz
21:16:42 1166818602 FRB 9.999998405 MHz
21:17:48 1166818668 RAB 0.999998619
21:18:55 1166818735 FRA 9.999984597 MHz

Greetings from Germany,

    Chris

----- snip (reduced version) -----
#!/usr/bin/tclsh8.4

# callback when there is reable data on the serial port
proc getData { chan } {
        if { [eof $chan] } {
                return
        }
        # get one line from serial port
        set s [gets $chan]

        # form timestamp
        set t [clock seconds]
        set f [clock format $t -format "%H:%M:%S"]

       # print timestamp
        puts "$f $t $s"
}

set sp [ open "/dev/ttyS0" "r+" ]
fconfigure $sp -blocking 0 -mode "9600,n,8,1" -handshake none -buffering 
line
fileevent $sp readable [ list getData $sp ]

set quit 0
while { $quit == 0 } {
        vwait quit
}

----- full script ----
#!/usr/bin/tclsh8.4

set currchan ""

proc getData { chan } {
        global currchan

        if { [eof $chan] } {
                return
        }

        # get one line from serial port
        set s [gets $chan]

#       puts "chan << $s"

        # check if it looks like a number (starts with 0-9)
        # if there is no recent measurement, the counter will
        # respond with "Not available" or such.
        if { ! [string match "\[0-9.\]*" $s ] } {
                return
        }

        # form header
        set t [clock seconds]
        set f [clock format $t -format "%H:%M:%S"]

        # print timestamp, unix seconds, string from counter
        if { "" != "$currchan" } {
                puts "$f $t $currchan $s"
        }

        # Advance channel.
        switch $currchan {
                FRA { set currchan "FRB" }
                FRB { set currchan "RAB" }
                default { set currchan "FRA" }
        }

        puts $chan "$currchan"
}

# send "XMT" to counter, which tells the counter to return
# the most recent measurement
proc doTick { chan } {
        puts $chan "XMT"

        after 1000 [ list doTick $chan ]
}

set sp [ open "/dev/ttyS0" "r+" ]
fconfigure $sp -blocking 0 -mode "9600,n,8,1" -handshake none -buffering 
line

fileevent $sp readable [ list getData $sp ]

# input channel A AC, 50 Ohm, 1:10
puts $sp "ACA"
puts $sp "OAL"
puts $sp "LVA0.00"
puts $sp "AA1"
# input channel B
puts $sp "ACB"
puts $sp "OBL"
puts $sp "LVB0.00"
puts $sp "AB1"

# gate time: 65535 ms
puts $sp "SMT65535"

# poll counter every 1000 ms
after 1000 [ list doTick $sp ]

set quit 0
while { $quit == 0 } {
        vwait quit
}