2. Serial RapidIO Interface > Multicast Event Control Symbols
55
Tsi578 User Manual
June 6, 2016
Integrated Device Technology
www.idt.com
2.5
Multicast Event Control Symbols
Multicast-Event Control Symbol (MCS or MCES) forwarding describes the process where an MCS
received on one RapidIO port is propagated out other RapidIO ports.
When a RapidIO port receives an MCS, it signals all other ports of the fact that an MCS was received.
Each port can optionally transmit an MCS when it is notified that an MCS has been received by another
port. A port is forwarded an MCS when the MCS_EN bit is set in the
“RapidIO Serial Port x Control
.
2.5.1
MCS Reception
When a RapidIO port receives a MCS, it does the following:
•
Raises an interrupt that can be masked.
— Interrupts are masked when the port’s MCS_INT_EN bit is set in
•
Forwards the symbol to all the other RapidIO ports
— Each port then forwards the control symbol if its MCS_EN field in the
is set to 1.
Per-port interrupt status appears in the MCS field in the
“RapidIO Port x Multicast-Event Control
Symbol and Reset Control Symbol Interrupt CSR” on page 312
. Additionally, the logical OR of all
per-port Multicast Event interrupt status is available in both the MCS field in the
Multicast-Event Control Symbol and Reset Control Symbol Interrupt CSR” on page 312
and the MCS
field in the
“Global Interrupt Status Register” on page 388
Interrupts can be cleared, either per-port or for all ports, by writing 1 to the MCS field in the
Port x Multicast-Event Control Symbol and Reset Control Symbol Interrupt CSR” on page 312
.
Additionally, the MCES pin in the Tsi578 can output an edge when an MCS is received. The MCES pin
toggles to signal an MCS is received; that is, the first MCS causes the pin to go low and the second
MCS causes it to go back high. The ports that are used as the source for toggling this MCES pin is
selectable using the MCS_INT_EN bit in the
“RapidIO Port x Mode CSR” on page 310
. To select the
MCES pin as an output, set the MCES_CTRL to 10 in the
“MCES Pin Control Register” on page 394
.
Ti
p
Multicast-Event control symbols (MCS) are explained in detail in the
RapidIO Interconnect
Specification (Revision 1.3)
.
Due to the finite time it takes to translate an MCS to a signal on the MCES pin, the minimum
time between any two MCS received in the Tsi578 is 500 ns. The second MCS can be lost if
this condition is not met.