Freescale Semiconductor SC140 specifications Instruction Set Accelerator Plug-In

5.5.5	Fast Return from Subroutines	5-36
5.6	Working Modes	5-37
5.6.1	Normal Working Mode	5-37
5.6.2	Exception Working Mode	5-37
5.6.3	Typical Working Mode Usage Scenarios	5-38
5.6.3.1	Dual-stack RTOS	5-38
5.6.3.2	Single-stack RTOS	5-39
5.6.4	Working Mode Transitions	5-39
5.6.4.1	From Exception to Normal mode	5-39
5.6.4.2	From Normal to Exception mode	5-39
5.7	Processing States	5-41
5.7.1	Processing State Change Instructions	5-41
5.7.2	Processing State Transitions	5-42
5.7.3	Execution State	5-43
5.7.4	Reset Processing State	5-43
5.7.5	Debug State	5-44
5.7.6	Wait Processing State	5-44
5.7.7	Stop Processing State	5-45
5.8	Exception Processing	5-46
5.8.1	Interrupt Vector Address	5-48
5.8.1.1	Vector Base Address Register	5-48
5.8.1.2	Programming Exception Routine Addresses	5-48
5.8.2	Return From Exception Instructions	5-49
5.8.3	Maskable Interrupts	5-50
5.8.3.1	Interrupt Priority Level	5-50
5.8.3.2	Controlling All Interrupt Sources	5-50
5.8.4	Non-Maskable Interrupts (NMI)	5-50
5.8.5	Internal Exceptions	5-50
5.8.5.1	Illegal Exception	5-51
5.8.5.2	DALU Overflow	5-52
5.8.5.3	TRAP Exception	5-52
5.8.5.4	Debug Exception	5-52
5.8.6	Exception Interface to the Pipeline	5-52
5.8.6.1	Exception Routine Fetch	5-52
5.8.6.2	Exception Mode Execution	5-53
5.8.7	Exception Timing	5-53

Chapter 6

Instruction Set Accelerator Plug-In

6.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-57 6.2 ISAP - SC140 Schematic Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-58

6.2.1 Single ISAP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-58

6.2.2 Multiple ISAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-59 6.3 ISAP instructions and instruction encoding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-60 6.4 ISAP Memory Access. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-606.5 ISAP-core register transfers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-61 6.6 Immediate Data Transfer to ISAP registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-62

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