RealView ICE v1.1, or firmware patch 136 or later from web download, supports cores running at very low speed (down to 13 Hz). If you are having problems connecting to or debugging a slow core, please upgrade to the latest RealView ICE software and firmware.

RealView ICE firmware v1.1 includes a new option "JTAG Timeouts Enabled" in the Device Properties window of the RVConfig application. By default this option is set, but it can be cleared to disable RealView ICE hardware timeouts. If you clear this option when RealView ICE is configured in adaptive mode, RTCK can be stopped without RealView ICE reporting an error.

RealView Debugger also has an internal timeout that checks the communication with the RealView ICE box. You can configure the length of this timeout by adding the environment variable SCC_TIMEOUT, which specifies a timeout in milliseconds.

When working with very slow targets (less than 1KHz), both the RealView ICE and RealView Debugger timeouts should be disabled, so you need to do all the following:

• Configure RealView ICE in adaptive mode and provide RTCK
   
• Disable the option "JTAG Timeouts Enabled" in RVConfig
   
• Set SCC_TIMEOUT with a very large value (for example, if you set it to 10000000 you can forget totally about timeouts)

Note that auto-configuration is unlikely to work with a very slow core clock, so you may need to select the core template in RVConfig manually.