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Firmware 25.6 for MIPEX-02-1-X-X.1 X (CnHm)
Firmware 24.6 for MIPEX-02-3-X-X.1 X (СО2)
RELEASE NOTES
1. Important algorithm changes:
1.1 Zeroing procedure improvemnts:
Automatic zeroing of “negative concentration” values in any case has been removed from algorithm.
Zero autocorrecting in now is executed in narrow range ±3% LEL (±0.1% Vol. CH4) for positive and negative
concentration values.
This MIPEX-02 firmware changes requires adaptation in firmware of host device.
There are need to be added the monitoring of status byte/word. As the result of
monitoring of status the end-user must be informed that manual zero correction
should be done or zeroing procedure could be performed by host-device itself
when safe conditions are confirmed (see recommendations table in article 3 below
and User manual rev. 1.34 for details).
The changes are made to prevent the errors raise presented in previous auto zeroing algorithm.
For example, new algorithm suppresses zero shift error in case of condensed moisture on optical elements. New
algorithm excludes appearance of error caused by incorrect auto zeroing compensation at the endpoints of
temperature range.
New manual zeroing procedure allows correcting readings even in case of nonlinear zero shift in whole
temperature range (see User manual rev. 1.34 Appendix E. for details).
1.2 Special low-power mode
Additional low-power mode is included in firmware by increasing of pulses duty cycle of IR light source.
On/off switching is sending LOWPW1/ LOWPW0 commands which is available in OEM control mode.
In low-power mode (LOWPW1) response time (T90) could be worse than specified
for standard mode (LOWPW0). Low-power mode can be used only as indicative
mode.
2. Communication protocol changes:
2.1 @*0 command turns off @*X cycled short responses.
2.2 CALB3 command writes one and the same scaling coefficient for two ranges (counterpart of sequence of
CALB1 and CALB2 commands sending).
2.3 Response on CRC command is changed (see User manual rev. 1.34 in article 4.4).
3. Changes in status word/ status byte (marked with yellow):
Status word equal to “00” corresponds to all bits in status byte are 0 means, that transducer works properly.
MIPEX-02 FIRMWARE ver. 2x.6 Release notes rev. 1.0
www.mipex-tech.com
1
DATAE
command
1)
status byte
Bit 0
Bit 1
F/CFS/CCS/CKS
command
1) 2)
status Word
Title
Description
Performance
according to
Table A.2
Recommendations
Deterioration
possible
1. Do not perform calibration.
2. Zeroing is acceptable If
concentration reading is not “-1”
Unspecified
performance
1. Do not perform calibration or
zeroing.
2. Replace transducer, if bit1 is on
constantly (> 20 min).
3)
10
Self-diagnostics
Self-diagnostics
algorithm is in action
during not more than
3.5 minute after power
up.
50
Abrupt change of
signal
Abrupt change of signal
or high noise level.
Low signals level
Low level of optical
signals because of:
1. Optical mirrors in
sensor hazed by dirt.
2. Optoelectronic
components are
degraded by time.
3. Optocomponents are
destructed by the high
level of temperature,
pressure or humidity.
4. Housing
deformation.
Unspecified
performance
1. Do not perform calibration or
zeroing.
2. Measuring accuracy need to be
additionally verified, once
switching on of Bit 2 has been
observed.
3. Replace the sensor if Bit2 is on
constantly (> 20 min).
Bit 2
30
Bit 3
reserved
Bit 4
21
Fast temperature
change
Temperature change
rate is higher than 0.6
grad/min
Deterioration
possible
Do not perform calibration or
zeroing.
Bit 4 + Bit 9
24
Fast temperature
change + Zero shifts
to negative values
Temperature change
rate is higher than 0.6
grad/min
Deterioration
possible
Do not perform calibration or
zeroing.
Bit 5
22
Sharp temperature
change
Temperature change
rate is higher than 4
grad/min
Unspecified
performance
Do not perform calibration or
zeroing.
Bit 5 + Bit 9
22
Sharp temperature
change+ Zero shifts to
negative values
Temperature change
rate is higher than 4
grad/min
Unspecified
performance
Do not perform calibration or
zeroing.
Out of operation
temperature range
Environmental
temperature is higher
0
than 60 C or lower
0
than-40 C.
Unspecified
performance
1. Do not perform calibration or
zeroing.
2. Measuring accuracy need to be
additionally verified, once
switching on of Bit 6 has been
observed.
Firmware corruption
MCU corruption or
maximum number of
flash writing circles is
exceeded.
Unspecified
performance
Replace the sensor
Too many UART
interruptions
Request frequency is
higher than 1 Hz or
transducer is situated in
high level EMI.
Deterioration
possible
1. Do not perform calibration or
zeroing.
2. Decrease request frequency.
3. Shield the sensor from EM fields,
if request frequency < 1Hz
guarantied.
Bit 6
Bit 7
Bit 8
40
90
11
MIPEX-02 FIRMWARE ver. 2x.6 Release notes rev. 1.0
www.mipex-tech.com
2
DATAE
command
1)
status byte
Bit 9
F/CFS/CCS/CKS
command
1) 2)
status Word
31
Title
Description
Performance
according to
Table A.2
Recommendations
3)
Zero shifts to negative
values
The possible reasons:
1. Moisture
condensation on optical
surfaces.
2. Housing deformation.
3. Optocomponents
drift.
Unspecified
performance
1. Using of dust filters is
recommended to avoid moisture
or dust inside transducer. In case
of moisture ingress, unmounts
transducer off device, then dry it
during 4 hours minimum in warm
dry location.
2. Make zeroing procedure and
performance check, if 1-3 reasons
pointed in description column are
excepted.
Low power regime is
on.
See article 4.3 of
Appendix D for details.
XX- status word values
similar for normal
regime.
Deterioration
possible
To achieve full compliance to
declared specification turn on the
standard regime.
Bit 10
1XX
NOTES:
1. The table is given for bits in high logic level. All status byte goes with AND logic, i.e. separate bits switching. All status
words goes with OR logic, priority from higher to lower : 1XX, 90, 10, 11, 30, 40, 31, 22, 21, 50.
2. If transducer returns status words other, than specified here, please contact to technical support
support@mipex-tech.com.
3. The term “calibration” means using of CALB, CALB1, CALB2, CALB3 commands. The term “zeroing” means using of ZERO,
ZERO2 commands..
MIPEX-02 FIRMWARE ver. 2x.6 Release notes rev. 1.0
www.mipex-tech.com
3