This document describes the implementation of control for the Lake Shore 340 temperature controller used with the Gemini Near-infrared Integral Field Spectrograph (NIFS).

2 Applicable Documents

Document ID	Source	Title
	RSAA	NIFS Critical Design Review
	Lake Shore	User’s Manual Model 340 Temperature Controller
	Omega Engineering Inc.	CYC3211, CYC3212, CYC3214 Cryogenic Temperature Controller – Operator’s Manual

3 Introduction

The software support for the Lake Shore 340 temperature controller was based closely on the support for the Omega CYC3200 temperature controller written by Hubert Yamada for NIRI. The new tcon record that has been developed, can be used with either the Omega controllers or the Lake Shore.

4 Software Support

4.1 EPICS Records

Two types of records are used with the Lake Shore 340: a “tcon” record used to control the temperature and a suite of ai (analog-in) records, used to monitor various parameters of interest reported by the Lake Shore 340.

4.1.1 The tcon Record

Figure 1: The tcon record.

The tcon record developed for the Lake Shore 340 controller (Figure 1) is the same as that developed for the Omega CYC3200 with the addition of the LOOP port. This port determines which loop (1 or 2) of the Lake Shore controller that this record controls. In addition, the tcon record fixes a bug which allows the SETP port to be connected to other records, as is necessary with NIFS. If the tcon record is used with an Omega controller, then the LOOP port is ignored.

4.1.2 The ai Record

Ai records are used to connect to the Lake Shore’s temperature sensors and other measurements reported by the controller. The string connected to the INP link of the ai record indicates what is to be monitored and to which serial port it is connected. The general form of this string is:

port parameter-to-be-monitored channel

Each of the three words in the string is separated by whitespace, consisting of spaces and tabs. For example, to monitor the “mode” of channel 2, with the Lake Shore using /tyCo/2 as the serial port, the label would be:

/tyCo/2 mode 2

The full list of channels that can be monitored are listed in Table 1. Note that when monitoring “heat”, no channel is specified. More information about the meaning of these parameters can be found in the Lake Shore manual.

Table 1: Lake Shore 340 values which can be monitored through ai records.

Label	Format	Channel Range	Description
tmp	port tmp channel	1-4	Temperature
heat	port heat	N/A	% power into the heater
mode	port mode channel	1-2	Specifies data the analog output monitors: 0 = off, 1 = input, 2 = manual, 3 = loop.
high	port high channel	1-2	If mode is 1, then this is the data at which the analog output represents +100% of output.
low	port low channel	1-2	If mode is 1, then this is the data at which the analog output represents -100% of output if bipolar, or 0% output if positive output only.
manual	port manual channel	1-2	If mode is 2, this parameter is the output of the analog output.
error	port error channel	1-2	Indicates an error
source	port source channel	1-2	Specifies input data: 1 = Kelvin, 2 = Celsius, 3 = sensor units, 4 = linear equation.
bipolar	port bipolar channel	1-2	Specifies whether the analog output is bipolar or positive only.
input	port input channel	1-2	Specifies which input to monitor if mode = 2.

Figure 2 shows ai records configured for temperature monitoring and for power into the heater.

Figure 2: Analog-in records for the Lake Shore 340 Temperature Controller.

4.2 Record Support

Record support is in the file, recTcon.c. This supports both the Omega controller and the Lake Shore controller.

4.3 Device Support

Device support for tcon records, using the Lake Shore 340 controller is in devTconLS340.c. In EPICS, set DTYP to “Lakeshore 340”. For ai records use the same DTYP, viz. “Lakeshore 340”. Device support is in the devAiLS340.c file.

4.4 Device Driver

The one driver is used for all of the analog-in records and the tcon record. This driver is in the drvLS340 module. The driver can be configured (at compile time) to use either the XYCOM XY490 serial board, or the standard serial connectors on the CPU card. To use the XY490 board, in drvLS340.c use the #define

#define XY490.

To select the standard CPU board ports, use the #undef

#undef XY490.

4.5 ASCII Files

The devSup.ascii file in the ascii/cat_ascii directory, must have the following line added to it in order to use the Lake Shore 340

“ai” INST_IO devAiLS340 “Lakshore 340”

“tcon” INST_IO devTconLS340 “Lakeshore 340”

The drvSup.ascii file must also have the line

“drvLS340”

added to it.

In addition, the tcon record requires that the tconRecord.ascii and choiceTcon.h files be added to the ascii/cat_ascii directory.

4.6 Other Files

The definition file, edb.def in the capfast directory where the tcon record will be used needs to have the following entry made to it:

(RECORD "etcon" "etcons" "etconm" "etconsim"

(PV (char))

(Type "tcon")

(DESC (char))

(SCAN (char(default "Passive")))

(PINI (char(default "NO")))

(PHAS (int))

(EVNT (int))

(DTYP (char(default "Tmp Sim")))

(DISV (int))

(SDIS (char(default "0.000000000000000e+00")))

(DISS (char(default "NO_ALARM")))

(PRIO (char(default "LOW")))

(FLNK (char(default "0.000000000000000e+00")))

(OUT (char(default "0.000000000000000e+00")))

(LOOP (int(default "0")))

(PREC (char(default "0")))

(EGU (char))

(HOPR (int))

(LOPR (int))

(HIHI (int))

(LOLO (int))

(HIGH (int))

(LOW (int))

(HHSV (char(default "NO_ALARM")))

(LLSV (char(default "NO_ALARM")))

(HSV (char(default "NO_ALARM")))

(LSV (char(default "NO_ALARM")))

(HYST (int))

(ADEL (int))

(MDEL (int))

(SIOL (char(default "0.000000000000000e+00")))

(SIML (char(default "0.000000000000000e+00")))

(SIMS (char(default "NO_ALARM")))

)

4.7 Summary of Files Needed

ascii/cat_ascii/tconRecord.ascii

ascii/cat_ascii/choiceTcon.h

ascii/cat_ascii/devSup.ascii

ascii/cat_ascii/drvSup.ascii

include/rec/tconRecord.h

src/drvLS340.c

src/drvLS340.h

src/devAiLS340.c

src/devTconLS340.c

src/recTcon.c

src/recTcon.h

capfast/etcons.sym

capfast/edb.def

Appendix A: List of Figures

Figure 1	figure.gif