The SMYRF device.
Status:
The SMYRF device is now finished, and this documentation should be uptodate.
000724 JSN
The SMYRF device is part of the GPIBDevices project. See GPIBDevicesVersion for versioning. This documentation applies to version 1.1.36.38.
11/2-2010: It seems like the SMYRF device fails when the Autopolling on the GPIB general settings is enabled. THIS IS THE DEFAULT option for the controller - Disable autopolling in the device until the bug is fixed. See also ELOG entry 826.
Contents:
Overview:
The SMYRF device is used to interface a Rohde & Schwarz SMY01 Signal Generator controlled by GPIB. Most relevant functions have been implemented. This include RF frequency, RF level, Phase-, Frequency-, and Amplitude-Modulation (Word selectable to either off, internal, external AC/DC.
The device is presently (Sep98) used two places.
CRE31SMY: The frequency for the RF cavity for acceleration of the electron beam is now generated by a Rohde&Schwarz SMY01 Signal Generator. (Earlier it was generated by a homebuild RF generator). The reason for the change is the wish to phasemodulate the RF frequency to obtain a better lifetime of the electron beam.
KEV31SMY: Vertical excitation of the electron beam. We are now changing (using a table conversion) the excitation frequency as a function of undulator gap.
Note that in order to allow many fast changes there is no instrument status inquiry for parameters no. 0, 1, and 7 (frequency, modulation frequency, and RFlevel). This means that instrument specification can be exceeded without update of error parameter.
Device parameters:
For addressDefinition the device uses AddTypeId number 9 (One-dim address) which uses a0 to determine the parameter number.
parameter |
Suggested |
Parameter name |
Data Type |
Interpretation |
Comment |
0 |
freq |
Frequency [kHz or MHz depending on device configuration] |
Float |
Bipolar Floating. |
Deviation from the nominal frequency defined in the setup of the device. |
1 |
modFreq |
Modulation Frequncy [kHz] |
Float |
Unipolar Float. (no 136) |
The phase modulation frequency. |
2 |
phaseDevi |
Phase Modulation Deviation [rad] |
Float |
Unipolar Float. (no 137) |
The phase modulation deviation. |
3 |
phaseMod |
Phase Modulation control |
Control Word |
Word (no 252). |
0: PM off, 1: PM internal, 2: PM External AC, 3: PM Dual |
4 |
reset |
Resets the device |
(pulsed control bit) |
Bit, checkbox, push bottom (no 572). |
Writing a one to this parameter will reset the device, the GPIB connection, and the instrument. This should not be necessary very often, and should properly be a restricted parameter. |
5 |
error |
Error number |
Word |
Word. |
A zero indicated all is OK, and anything else that something is wrong. |
6 |
errStr |
Error String |
String |
String. |
Tekst string with error. |
7 |
RFLevel |
RF level [dBm] |
Float |
Bipolar Float (no 150) |
|
8 |
FMDevi |
Frequency Modulation Deviation [kHz] |
Float |
Unipolar Float (no 151) |
|
9 |
AMDevi |
Amplitude Modulation Deviation [%] |
Float |
Unipolar Float (no 152) |
|
10 |
FMMod |
Frequency Modulation Control |
Control Word |
Word (no 251). |
0: FM off, 1: FM internal, 2: FM External AC, 3: FM External DC, 4: FM Dual AC, 5: FM Dual DC |
11 |
AMMod |
Amplitude Modulation Control |
Control Word |
Word (no 251). |
0: AM off, 1: AM internal, 2: AM External AC, 3: AM External DC, 4: AM Dual AC, 5: AM Dual DC. |
12 |
RFon |
Level Control |
Control Bit |
Bit, checkbox (no 517). |
A high (true) means that the RF signal is on and a low (false) means it is off. |
Device configuration:
The following parameters are setup by the ConsysManager and stored in the .config file at the front-end computer on which the device is loaded:
- GPIB address (default is 10)
- RF offset frequency ()
- RF freq. UNIT (kHz or MHz)
Description of setup:
This section is empty.
Last Modified 05 February 2020