Access from the user program
KL320x
47
Version: 4.4
• Gain compensation is then carried out independently of the offset, e.g. at 300 Ω. 300 Ω corresponds to
557.7°C = 0x15C9
5.6.4
Default setting of the registers
• R17: 0xED68 corresponds to -90.8 Ω
• R18: 0x4E20 corresponds to 2000 * 16-5 = 0,01907 Ω/digit
• R19: 0x0000
• R20: 0x00A0
• R32: 0x0106
• R33: 0x0000
• R34: 0x0100
The gain and offset compensation only has to be carried out once, i.e. it does not have to be repeated or
corrected for any of the other implemented elements.
For the two-wire connection, with short-circuited line resistance (+R1-Rl1) the raw ADC value of the line
resistance (contained in R1) has to be entered in register R21.
5.6.5
KL3202 as resistance input 0 to 1 kΩ
If the KL3202 is used for resistance measurements, the following values should be written into the following
registers:
• R32: Feature register: 0xF401
i.e. user scaling active with display of the measured value in Ohm and two-wire connection.
• R33: User scaling - offset (0x0000)
• R34: User scaling - gain (0x0010)
the display of the measured value follows:
Resistance in Ω
Output value
0
0
1000
1000
5.7
Register communication
5.7.1
Register access via process data exchange
Bit 7 = 1
bin
: Register mode
If bit 7 of the control byte is set, then the first two bytes of the user data are not used for exchanging process
data, but are written into or read from the terminal's register set.
Bit 6 = 0bin: read
Bit 6 = 1bin: write
Bit 6 of the control byte specifies whether a register should be read or written. If bit 6 is not set, then a
register is read out without modifying it. The value can then be taken from the input process image.