MKS SM1690 Series, Technical Notes

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SM 1690
page 8 of 18 File: SM1690_r5eng - Dec. 2013 - Technical note: SM1690
SM 1690 SM 1280
SM 1690
File: SM1690_r5eng - Dec. 2013 - Technical note: SM1690 page 9 of 18
MW
-
ON
: starts microwave emission at the presetted power level
while the led “MW ON” is lighted up.
The unit exits from this mode in case of:
* the enabling command is set OFF: enters into Ready state, or
* ALARM presence: the unit goes to Stand-by, or
* the INTERLOCK chain is open: it goes to Stand-by again.
* the Hibernate command is set to ON: jump to Stand-by.
Meaning of external commands.
HIBERNATE: has value ON/OFF. If ON the magnetron’s
filament is not powered and the SM1690x goes into Stand-by
mode.
In OFF the unit makes filament heating and, when the related
timer is elapsed, enters in Ready mode.
If a user don’t like to use the Hibernate function, he may not
connect the HIBERNATE control signal: the system then
detect it as in OFF condition.
POWER ENABLE: has value ON/OFF, but its effect is related
also with the Hibernate command as follow:
a) in OFF state - and HIBERNATE is OFF - the unit performs
filament preheating and goes in Ready mode but does not
generate output power, even if the reference signal is >0;
b) in OFF state - and HIBERNATE is ON - the unit is in
Stand-by mode but does not generate output power, even if the
reference signal is >0;
c) in ON state - and HIBERNATE is OFF - the unit waits the
end of preheating timer, if not yet elapsed, then starts to gene-
rate output power;
d) in ON state - and HIBERNATE is ON - the unit is in Stand-
by mode but does not generate output power, even if the
reference signal is >0.
POWER SET: it’s an analog input value and has the meaning
of “desired percent” of the full output power (14000W)
When this value is lower than 1Vdc the unit does not gene-
rate any output power, when >1Vdc the unit generates power
proportional to this signal value.
The CPU drives the unit to obtain an electrical output power
(Va * Ia) value proportional in a linear way to the reference
input signal. The scaling is 1400W/V.
INTERLOCK: it is an external hardware chain of contacts,
that must be closed all at the time to have the internal relay
closed. (ON condition). When in ON the CPU light-up the
related Interlock OK led; in OFF state the led is Off and the
unit goes in Stand-by, as all dangerous voltages on the head
connector are off.
Firmware upgrade
The software stored on the CPU (firmware, on a flash
memory) can be upgraded to a newer version using the RS232
serial port on the unit, connected to a PC.
Important remark: at power-on, even if a program is already
stored, the microprocessor enters a “BOOTLOADER” status,
lasting 2 seconds, during which it is possible to overwrite,
through the serial RS232 port, the stored code.
If no new code is loaded within 2 seconds, the previously stored
one is run.
To upload a new program through the bootloader, simply
connect the SM1690x serial port to the PC serial port, using a 9
pin 1:1 cable (only TX, RX and Ground are used, but also a full
cable will fit. See schematic on page 11)
No external switch must be operated, and the unit does not start
until the new program is stored, but be sure no enable signal is
active when upgrading.
The upgrade of the firmware embedded in the SM1690x is
released as a .zip archive named “ program_name.zip ”.
Unpacking the .zip archive you generate:
- a directory named “ program_name ” containing the micro
code to be loaded,
- an executable program named “ SendApplicationProgram.bat
”- the loader “ sRecLoad.exe ”,
- and the library “ Nican.dll ”.
Once unpacked the .zip program:
- enter in the folder “ program_name ”,
- switch-on the SM1690x
- run whithin 2 seconds the program “ SendApplicationProgra-
m.bat ” (which launches sRecLoad.exe application)
(This is the maximum time that the microprocessor bootloader
waits for new code to be loaded).
During the bootloader wait time, the red ALARM led is on: if
no code is sent, then the previous code is executed, and it is not
possible to change it without switching the unit off.
In case the program sRecLoad.exe sends data whithin 2
seconds, the microprocessor bootloader stores the new data
on the internal flash memory, installing the new release, and
automatically executes it when the download is done.