Intel® Quartus® Prime Standard Edition User Guide: Platform Designer

ID 683364
Date 12/15/2018
Public
Document Table of Contents

3.14.13. Avalon® Tristate Conduit Signal Roles

The following table lists the signal defined for the Avalon® Tristate Conduit interface. All Avalon® -TC signals apply to both masters and slaves and have the same meaning for both
Table 80.  Tristate Conduit Interface Signal Roles
Signal Role Width Direction Required Description
request 1 Master → Slave Yes The meaning of request depends on the state of the grant signal, as the following rules dictate.

When request is asserted and grant is deasserted, request is requesting access for the current cycle.

When request is asserted and grant is asserted, request is requesting access for the next cycle. Consequently, request should be deasserted on the final cycle of an access.

The request signal deasserts in the last cycle of a bus access. The request signal can reassert immediately following the final cycle of a transfer. This protocol makes both rearbitration and continuous bus access possible if no other masters are requesting access.

Once asserted, request must remain asserted until granted. Consequently, the shortest bus access is 2 cycles. Refer to Tristate Conduit Arbitration Timing for an example of arbitration timing.

grant 1 Slave → Master Yes When asserted, indicates that a tristate conduit master has access to perform transactions. The grant signal asserts in response to the request signal. The grant signal remains asserted until 1 cycle following the deassertion of request.
<name>_in 1 – 1024 Slave → Master No The input signal of a logical tristate signal.
<name>_out 1 – 1024 Master → Slave No The output signal of a logical tristate signal.
<name>_outen 1 Master → Slave No The output enable for a logical tristate signal.