Chapter 10 XGATE (S12XGATEV3)
MC9S12XE-Family Reference Manual , Rev. 1.19
Freescale Semiconductor
353
•
Provides up to 108 XGATE channels, including 8 software triggered channels
•
Interruptible thread execution
•
Two register banks to support fast context switching between threads
•
Hardware semaphores which are shared between the S12X_CPU and the XGATE module
•
Able to trigger S12X_CPU interrupts upon completion of an XGATE transfer
•
Software error detection to catch erratic application code
10.1.3
Modes of Operation
There are four run modes on S12XE devices.
•
Run mode, wait mode, stop mode
The XGATE is able to operate in all of these three system modes. Clock activity will be
automatically stopped when the XGATE module is idle.
•
Freeze mode (BDM active)
In freeze mode all clocks of the XGATE module may be stopped, depending on the module
configuration (see
Section 10.3.1.1, “XGATE Control Register (XGMCTL)”
).
10.1.4
Block Diagram
shows a block diagram of the XGATE.
Figure 10-1. XGATE Block Diagram
Interr
upts
XGA
TE
Requests
S12X_MMC
XGATE
Peripherals
Semaphores
Software Triggers
Peripheral Interrupts
S12X_DBG
Data/Code
Software
Triggers
XGA
TE
S12X_INT
SWE
Interrupt
RISC Core
Software Error Logic
Interrupt Flags
(XGIF)
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:
S12XE
products
in
208
MAPBGA
packages