For the Enhanced Mini-ACE™, what is the minimum BC inter-message gap time?
A. For the Non-Enhanced BC mode (i.e., not using the autonomous BC message sequence control engine), the nominal BC intermessage gap time for the Enhanced Mini-ACE™ is the same as for the Mini-ACE™ (Plus) hybrids, approximately 9.5 µs. However, for the Enhanced Mini-ACE™’s enhanced BC mode (using the autonomous message sequence control engine), the typical value for intermessage gap time is approximately 10 clock cycles longer than for the non-enhanced BC mode. This accounts for the time for the message sequence control engine to fetch op code and parameter words from the BC Instruction List, and to execute the op code (assuming an Execute Message (XEQ) instruction). That is, an additional 1.0 µs at 10 MHz, 833 ns at 12 MHz, 625 ns at 16 MHz, or 500 ns at 20 MHz. Also, note that if ENHANCED CPU ACCESS, bit 14 of Configuration Register #6, is set to logic “1”, the Enhanced Mini-ACE™’s arbitration logic will interleave host transfers in between individual SOM or EOM word transfers. In th
