# Communication timeout w/DigiOne SP **URL:** \ **Category:** Realport\ **Created:** [June 7, 2011, 5:24pm UTC](https://forums.digi.com/t/communication-timeout-w-digione-sp/7353 "2011-06-07T17:24:34Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![pkahn](https://avatars.discourse-cdn.com/v4/letter/p/dfb087/32.png) [@pkahn](https://forums.digi.com/u/pkahn)\ **Post date:** [June 7, 2011, 5:24pm UTC](https://forums.digi.com/t/communication-timeout-w-digione-sp/7353/1 "2011-06-07T17:24:34Z")
I just purchased a DigiOne SP for use with an embedded product. Some basic info: - The serial parameters are fixed at 56K, 8, 1, no flow. - The communication protocol is proprietary and binary. - The PC is the master and the embedded device is the slave. - The PC sends a request and the embedded device must respond within 10 to 50 msec depending on the command/query. - The Windows software connects to a COM port and uses the standard Win32 API. It has worked on Windows XP for many years. - Using standard Win32 API for reading/writing: CreateFile(), ReadFile(), etc. - Adjusting comm parameters via SetCommTimeout() and SetCommState(). - We also use this product with the Digi EdgePort (4) USB and have had no issues. Not knowing any better, I configured the DigiOne for use with the RealPort driver. The connection basically worked but the Windows client frequently dropped packets (responses) due to timeouts. I then adjusted the configuration in the Advanced Serial Settings so that the inter-character timeout was enabled and set to 1 msec. However, I still frequently encounter dropped packets from the embedded device. If I place a small delay (~5msec) in the communications thread this problem appears to go away. However, I wonder if there is another parameter I could set to force the RealPort driver to flush it’s buffers more frequently. I suspect that is the source of the problem. I see the same behavior (albeit worse) on Windows 7; I am using the Windows 7 driver downloaded from the web site. Thanks in advance for any help…