GSP-1600 Data Port Flow Control (TB-06-02)
A full discussion of GSP-1600 Data Port Flow Control is provided in Technical Bulletin TB-06-02.
For convenience the text of the technical bulletin is provided below.
This technical bulletin is only relevant to GSP-1600 phones with firmware versions R5.3 and R5.4 and only if you are using the GSP-1600 for data communications. To determine the firmware version on the GSP-1600, press the MENU “softkey”, followed by the digits “8” and “3”. The firmware version will be shown on the second line of the display.
If you are not using the GSP-1600 for data communications, or if your GSP-1600 does not have firmware version R5.3 or R5.4, then there is no need to read further.
Data communication over the GSP-1600 is carried out via an RS232 data interface. Configuration of the RS232 port is described in detail in the GSP-1620 Integrator’s Reference Manual. Of particular interest to this technical bulletin, the GSP-1600 data port is supposed to be able to use either hardware or software flow control in either direction.
Tests by Globalstar and users indicate that flow control is not working properly in firmware versions R5.3 and R5.4. This flow control problem becomes evident primarily when sending data from the Globalstar-connected device through the GSP-1600 and the Globalstar satellites to the landline destination.
Many applications can deal with this lack of flow control. However, if a computer or device is having difficulty sending data from the GSP-1600 phone to the network, then it is possible that flow control is to blame. If you believe that you are experiencing this problem, call Globalstar Customer Care so that they can help diagnose and troubleshoot the problem.