Appendix
3
Cole Palmer
The master sets parameters in the chiller by sending one of the Set Functions as shown in Table 1. The master
does not send a qualifier byte in the data field. The master should be preprogrammed to send the correct precision
and units (it could also read the parameter of interest first to decode the correct precision and units needed).
As an example, if the master wants to set the setpoint to 30°C, it would send :
Table 1
Commands (All bytes are in hex)
FUNCTION
MASTER SENDS
UNIT RESPONDS
Read Acknowledge
CA 00 01
00
00 FE
CA 00 01
00
02(v1)(v2)(cs)
Read Status (see Table 3)
CA 00 01
09
00 F5
CA 00 01
09
02(d1)(d2)(cs)
Error
CA 00 01
0F
02(en)(ed)(cs)
Read Internal Temperature (RTD1)
CA 00 01
20
00 DE
CA 00 01
20
03(qb)(d1)(d2)(cs)
Read External Temperature (RTD2)
CA 00 01
21
00 DD
CA 00 01
21
03(qb)(d1)(d2)(cs)
Read Setpoint One
CA 00 01
70
00 8E
CA 00 01
70
03(qb)(d1)(d2)(cs)
Read Low Temperature Warning
CA 00 01
40
00 BE
CA 00 01
40
03(qb)(d1)(d2)(cs)
Read Low Temperature Fault
CA 00 01
41
00 BE
CA 00 01
41
03(qb)(d1)(d2)(cs)
Read High Temperature Warning
CA 00 01
60
00 9E
CA 00 01
60
03(qb)(d1)(d2)(cs)
Read High Temperature Fault
CA 00 01
61
00 BE
CA 00 01
61
03(qb)(d1)(d2)(cs)
Read Cool Proportional Band (P)
CA 00 01
74
00 8A
CA 00 01
74
03(qb)(d1)(d2)(cs)
Read Cool Integral (I)
CA 00 01
75
00 89
CA 00 01
75
03(qb)(d1)(d2)(cs)
Read Cool Derivative (D)
CA 00 01
76
00 88
CA 00 01
76
03(qb)(d1)(d2)(cs)
Read Heat Proportional Band (P)
CA 00 01
71
00 8D
CA 00 01
71
03(qb)(d1)(d2)(cs)
Read Heat Integral (I)
CA 00 01
72
00 8C
CA 00 01
72
03(qb)(d1)(d2)(cs)
Read Heat Derivative (D)
CA 00 01
73
00 8B
CA 00 01
73
03(qb)(d1)(d2)(cs)
command bytes shown in
bold
v1, v2 = protocol version
qb = qualifier byte, see Table 2
ed Bad command byte gets echoed)
d1,d2 = 16 bit signed integer of the value being
en (error number) 01 = Bad command,
sent or received
02 = Bad checksum
cs = the checksum of the string (see text)
xx = no valid data, include in checksum
CA 00 01 F0 03 11 01 2C CD
command byte
3 bytes to follow
The checksum is the bitwise inversion of 22
(00+01+F0+03+01+2C)
Take the LSB=32
The qualifier byte of 11 indicates a precision of 1
decimal point and units of °C. The temperature of
30°C is 300 decimal = 012C hex.
command byte
2 bytes to follow
The checksum is the bitwise inversion of 20
(00+01+F0+02+01+2C)
Take the LSB=22
The temperature of 30.0°C is 300 decimal = 012C hex.
CA 00 01 F0 02 01 2C DF
Unit responds:
unit address
(defaults to 01)
unit address
