remember to close port after use
maybe break up into open and close port functions



gui
----------------
time strip chart
save data to file as it comes in

time before heat pulse

power of pulse

start/stop button

port

log filename

heating time

log interval

in file:

time tt t2 t3 t4 tb H 0

value after H is the heater value

tt is temp top of probe
tb is temp bottom

H 

Display a HELP message, including the probe's firmware number and date.
(Sending #HFH and getting a response is a quick way to check communications with the probe.

N

Report the probe's serial number. This command returns a space and a single hexadecimal character. For serial numbers ten or greater, only the ones digit is returned.

T
View the 7 current TIME_INTERVALS.
The probe's response to the T command is a space and 8 sets of four hexadecimal characters, separated by spaces. For example:

A138 A12F 207C 31F1 31F6 3629 372B 3902

shows the time interval values for the two resisters and five thermisters. The first number is to be ignored, the second is for the 100 KOhm resister, the third is for the 20KOhm resister, and the fourth through eighth are for the top through bottom thermisters respectively. The last file values would be interpolated between the second and third to result in the resistances of five therministers. From these, the Steinhart and Hart thermister model is used to calculate temperature. (These values all indicate near room temperature.)


!Phh

Set the heater POWER_LEVEL to the value hh. THe hh value must be followed by a space. This command returns no response.

S
Report the current heater POWER_LEVEL. This command returns a space and two hexadecimal characters.


!Qtttt hh

Set the heater POWER_LEVEL to the value hh for tttt seconds. The hh value must be followed by a space. This command returns no response.

