Townshend Computer Tools DAT-Link - Comdisco Systems SPW

102 Third Party Supp ort
11.1.2 Comdisco Systems SPW
Reading and Writing SPW Files
The naplay program can read SPW version 3.0 les that are stored in either oating
point or xed-p oint formats with up to 16 bits/sample by using the -fSPW option.
Both scalar and complex (stereo) signals are supported.
During record, narecord will store the les as 16 bit xed-p oint les if the -fSPW2
or -fSPW3 option is specied. Stereo recordings will b e saved as SPW complex les.
Values in the le header will b e lled in with appropriate values.
Using the DAT-Link from SigCalc
Comdisco's Signal Display Editor (SigCalc) provides graphical waveform display
and editing using the X Window System. This optional software is installed only
if the Comdisco support option was selected during the software installation. In
addition, you will need to p erform some additional steps to inform SPW of the
existence of the new user functions.
The DAT-Link executables for SPW support are stored in the sub directory of the
install directory, lib/dl/spw3.0 . You must create a link to these from the normal
Comdisco user program directory, /spwdata/sdeprog . To do this you will to su
to ro ot or the SPW maintainer. For example, if you installed the executables in
/usr/lo cal , use:
su
Password: xxxxx
rm -rf /spwdata/sdeprog/datlink
ln -s /usr/local/lib/dl/spw3.0 /spwdata/sdeprog/datlink
exit
You must then start mfileman and select Create... from the Libraries menu.
Select  SigCalc Metho d from the options at the top of the dialog that mfileman
will then present, and type datlink as the library name in the box lab elled Library .
The completed dialog should app ear as shown in Figure 11.4. This will inform SPW
of the existence of the new user functions.
Once the DAT-Link software is installed, you can start SigCalc and access the DAT-
Link functions from the Tools->User Programs->Execute... menu. Additional
menu options will then be available for playback, recording, and control of the DAT-
Link . A screen dump of the playback dialog for SigCalc is shown in Figure 11.5.
The various settings for record and playback can be easily specied using these
dialog boxes. Also, a transp ort menu can be used to control the DAT machine via