class Ppms

def initialize(adrs=15)
	@gpib=Gpib::new
	@gpib.pad=(adrs); @gpib.sad=0; @gpib.tmo=Gpib::T1s
	@gpib.open(0); sleep 0.1; @gpib.ibclr
	@gpib.write("*CLS")
	@temp,@field,@pres,@status=0,0,0,0
	read_data
	@temp_set,@temp_rate,@temp_cond=read_temp
	@field_set,@field_rate,@field_cond,@field_mode=read_field
	@level;read_level
end

attr_reader :temp
attr_reader :field
attr_reader :pres
attr_reader :status
attr_reader :temp_set
attr_reader :temp_rate
attr_reader :temp_cond
attr_reader :field_set
attr_reader :field_rate
attr_reader :field_cond
attr_reader :field_mode
attr_reader :level
#attr_accessor :

# constants
Status_temp=["unknown","normal stability","stable","","","tolerance","not valid","filling","","","standby","","","disable","incomplete","failure"]
Status_field=["unknown","persistent","warming","cooling","stable","approach","charging","discharging","error","","","","","","","failure"]
Status_chamber=["unknown","purge/seal","vent/seal","seal","under purge/seal","under vent/seal","","","pumping","flooding","","","","","","failure"]
Cond_temp=["fast settle","no overshoot"]
Cond_field=["linear","no overshoot","oscillate"]
Mode_field=["persistent","driven"]
Chamber_operation=["seal immediately","purge and seal","vent and seal","pump continuously","vent continuously"]

# set environment
def set_temp(tmp,rt=@temp_rate,cnd=@temp_cond)
# K,K/min
#Cond_temp=["fast settle","no overshoot"]
	@temp_set=tmp; @temp_rate=rt; @temp_cond=cnd
	@gpib.write(sprintf "TEMP %.2f %.1f %d",tmp,rt,cnd)
end
def set_field(fld,rt=@field_rate,cnd=@field_cond,md=@field_mode)
# Oe,Oe/sec
#Cond_field=["linear","no overshoot","oscillate"]
#Mode_field=["persistent","driven"]
	@field_set=fld; @field_rate=rt; @field_cond=cnd; @field_mode=md
	@gpib.write(sprintf "FIELD %.2f %.1f %d %d",fld,rt,cnd,md)
# persistent,driven
end
def shutdown()
	@gpib.write(sprintf "SHUTDOWN")
end

# read settings
def read_temp
	@gpib.write("TEMP?")
	return @gpib.read(256).split(/\s*,\s*/).collect{|e| e.to_f}[0..2]
end
def read_field
	@gpib.write("FIELD?")
	return @gpib.read(256).split(/\s*,\s*/).collect{|e| e.to_f}[0..2]
end
def read_level
	@gpib.write("LEVEL?")
	@level=@gpib.read(256).to_f
	return @level
end

# read present conditions
def read_data
#	0:status,1:temp,2:field,19:pressure
	flg=2**0+2**1+2**2+2**19
	@gpib.write("GETDAT? #{flg}")
	str=@gpib.read(256).split(/\s*,\s*/)
	num=str[2].to_i
	@temp=str[3].to_f
	@field=str[4].to_f
	@pres=str[5].to_f
#	@status="temp:"+Status_temp[num & 0xf]+",field:"+Status_field[num>>4 & 0xf]+",chamber:"+Status_chamber[num>>8 & 0xf]
	@status={
		"temp"=>Status_temp[num & 0xf],
		"field"=>Status_field[num>>4 & 0xf],
		"chamber"=>Status_chamber[num>>8 & 0xf],
		}
end

# chamber operation
def chamber(num)
#Chamber_operation=["seal immediately","purge and seal","vent and seal","pump continuously","vent continuously"]
	@gpib.write("CHAMBER #{num}")
end

end # class