Chapter 13 Miscellaneous Issues.

Click Topic for Quick Find:
1. When debugging, the application is deliberately forced to end and succeeding re-initialization fails. Why?
2. Can two applications supported by the same driver be run on one system?
3. When the application generates a smaller buffer for recording and uses a dual-buffer for playback, noise is heard in playback. Why?
4. Why does voice become intermittent during a playback with DTMF signals available on the line?
5. Why must the board be grounded?
6. The following prompts appear when the board is running: ‘The device driver for the ‘SHT-XXX-CT/PCI’ device is preventing the machine from entering standby. Please close all applications and try again’. Why?
7. What purposes do ShConfig.ini and ShIndex.ini serve in the application program?
8. How to install the SHT-16B-CT/PCI/MP3 board?
9. In a teleconference, how does the board prevent DTMF key tones in a channel from being heard by other channels?
10. Do Synway boards support event-driven programming?
11. Can the driver receive the original CallerID of a forwarded call?
12. Which programming platforms does the driver work on?
13. What is the difference among these three programming modes CALLBACK, EVENT_POLLING, and WINDOWS MESSAGE?
14. Why does the application sometimes not detect the change in call or monitoring status?


1. When debugging, the application is deliberately forced to end and succeeding re-initialization fails. Why?
Forced interruption during debugging prevents the memory of the board driver from being properly uninstalled. To avoid error, we advise calling the relative function to uninstall the board before ending the program.

2. Can two applications supported by the same driver be run on one system?
Yes, the driver supports multiple processes. However, different applications should run under separate directories, and the board cannot take function calls from different applications at the same time.

3. When the application generates a smaller buffer for recording and uses a dual-buffer for playback, noise is heard in playback. Why?
The default recording buffer size of the driver exceeds 800 bytes. When the application generates a buffer smaller than 800 bytes, the configuration file should be altered to turn on small-buffer recording.

4. Why does voice become intermittent during a playback with DTMF signals available on the line?
The driver is set by default to stop playback upon detecting DTMF signals, and intermittency could be due to the board driver picking up DTMF during playback. To prevent this from happening, set the value of ‘DefaultPausePlayOnRxDtmf’ under [BoardId=x] to 0 in the configuration file ‘ShConfig.ini’.

5. Why must the board be grounded?
A chassis installed with voice boards must be grounded for safety reasons, according to standard industry requirements. A simple way is earthing with the third pin on the plug. No or improper grounding may cause instability in operation as well as decrease in lightning resistance.

6. The following prompts appear when the board is running: ‘The device driver for the ‘SHT-XXX-CT/PCI’ device is preventing the machine from entering standby. Please close all applications and try again’. Why?
As the system is expected to run for long hours unmanned, ‘energy-saving’ mode should be turned off for both the CPU and the HD in CMOS or WINDOWS operating system. This is to ensure full-speed operation of the computer, or it may lead to a drop in performance or unexpected errors after running for some time.

7. What purposes do ShConfig.ini and ShIndex.ini serve in the application program?
Both ShConfig.ini and ShIndex.ini are necessary for driver configuration, and are where the system initialization function SsmStartCti() obtains information about models, numbers and DLLs of installed boards.

8. How to install the SHT-16B-CT/PCI/MP3 board?
The SHT-16B-CT/PCI/MP3 board supports MP3 recording in hardware and can be installed in the same way as other PCI boards. One thing to note is to set the item DSP3WorkMode to 3 in the configuration file ‘ShConfig.ini’ after installation.

9. In a teleconference, how does the board prevent DTMF key tones in a channel from being heard by other channels?
The board supports the DTMF-clamping feature that can prevent DTMF key tones from overflowing to other channels.

10. Do Synway boards support event-driven programming?
Yes.

11. Can the driver receive the original CallerID of a forwarded call?
Yes.

12. Which programming platforms does the driver work on?
The driver can work on all programming platforms that can directly invoke the standard Win32 interface, such as VB, VC++, .Net, DELPHI, C++BUILDER, PB, VFP, JAVA, etc.

13. What is the difference among these three programming modes CALLBACK, EVENT_POLLING, and WINDOWS MESSAGE?
EVENT_POLLING: Uses the polling mechanism and supports self-defined events.
WINDOW MESSAGE: Supports the WINDOW mechanism.
CALLBACK: Supports the callback mode.

14. Why does the application sometimes not detect the change in call or monitoring status?
Under the condition that the application uses the polling mode for programming and high frequency of interface refresh results in high CPU cost, such abnormal phenomena as failure to detect call or monitoring status may occur sometimes. Therefore, we suggest users optimize the application performance by using the event programming mode to reduce the cost of system resources.