Latency Timer Settings

If you are using a BASIC Stamp development board with a USB connector, or a serial board with a Parallax USB to Serial Adapter, you may need to adjust your computer's latency timer settings if any of these are true:

• The Run/Identify Test shows no Device Type, but a "Yes" in both the Loopback and Echo columns, or a "Yes" only in the Echo column.
• You have passed the Run/Identify test but when you try to download a program with Run/Run, you get a "No BASIC Stamps Found" message.
• You are able to download short programs, but not long ones.
• You are able to program intermittently, but sometimes it fails.

How to adjust the Latency Timer settings

• Using the Identification window from the Run/Identify Test procedure, make note of the COM port number in the row where it displays a "Yes" for Echo.
• Find that COM port in Device Manager.

Finding your Ports List in your computer's Device Manager

• Windows 2K: Start Menu > Settings > Control Panel > System > click Hardware Tab > Device Manager... > expand Ports (COM & LPT)
• Windows XP: Start Menu > right-click My Computer > Properties > click Hardware Tab > Device Manager > expand Ports (COM & LPT)
• Windows Vista or Windows 7: Start Menu (Windows icon) > right-click Computer > Properties > Device Manager (left pane) > expand Ports (COM & LPT)

• Right-click on the COM port, and select Properties

• Under the Port Settings tab, click the Advanced button.
• In the Advanced Settings window, change the Latency Timer setting to 1 and then click OK.

• Now try the Run/Identify Test again, or try downloading a program to your BASIC Stamp.
• If this did not help, Contact Parallax Tech Support for assistance..