S912XEG384J3VA Datasheet, PDF (355/1324 Pages) Freescale Semiconductor, Inc – MC9S12XEP100 Reference Manual Covers MC9S12XE Family

Chapter 10 XGATE (S12XGATEV3)
• 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
Figure 10-1 shows a block diagram of the XGATE.
Peripheral Interrupts
S12X_INT
XGATE
Interrupt Flags
Software
Triggers
SWE
Interrupt
Semaphores
Software Triggers
Software Error Logic
RISC Core
Peripherals
S12X_MMC
S12X_DBG
Figure 10-1. XGATE Block Diagram
MC9S12XE-Family Reference Manual Rev. 1.25
Freescale Semiconductor
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