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CHAPTER 7 INTERRUPT
7.6
Interrupt of Extended Intelligent I/O Service (EI
2
OS)
The extended intelligent I/O service (EI
2
OS) automatically transfers data between a
peripheral function (I/O) and memory. When the data transfer terminates, a hardware
interrupt is generated.
■
Extended Intelligent I/O Service (EI
2
OS)
The extended intelligent I/O service is a type of hardware interrupt. It automatically transfers data between
a peripheral function (I/O) and a memory. Traditionally, data transfer with a peripheral function (I/O) has
been performed by the interrupt processing program. EI
2
OS performs this data transfer in the same way as
direct memory access (DMA). At termination, EI
2
OS sets the termination condition and automatically
branches to the interrupt processing routine. The user creates programs only for EI
2
OS activation and
termination. Data transfer programs in between are not required.
●
Advantages of extended intelligent I/O service (EI
2
OS)
Compared to data transfer performed by the interrupt processing routine, EI
2
OS has the following
advantages.
•
Coding a transfer program is not necessary, reducing program size.
•
Because transfer can be stopped depending on the peripheral function (I/O) status, unnecessary data
transfer can be eliminated.
•
Incrementing or no update can be selected for the buffer address.
•
Incrementing or no update can be selected for the I/O register address.
●
Extended intelligent I/O service (EI
2
OS) termination interrupt
When data transfer by EI
2
OS terminates, a termination condition is set in the S1 and S0 bits in the interrupt
control register (ICR). Processing then automatically branches to the interrupt processing routine.
The EI
2
OS termination factor can be determined by checking the EI
2
OS status (ICR: S1, S0) with the
interrupt processing program.
Interrupt numbers and interrupt vectors are permanently set for each peripheral. See "7.2 Interrupt Causes
and Interrupt Vectors", in Chapter 7 for more information.
●
Interrupt control register (ICR)
This register, which is located in the interrupt controller, activates EI
2
OS, specifies the EI
2
OS channel, and
displays the EI
2
OS termination status.
●
Extended intelligent I/O service (EI
2
OS) descriptor (ISD)
This descriptor, which is located in RAM at 000100
H
to 00017F
H
, is an eight-byte data that retains the
transfer mode, I/O address, transfer count, and buffer address. The descriptor handles 16 channels. The
channel is specified by the interrupt control register (ICR).
Summary of Contents for MB90460 Series
Page 1: ...The following document contains information on Cypress products ...
Page 3: ......
Page 5: ......
Page 9: ...iv ...
Page 41: ...22 CHAPTER 1 OVERVIEW ...
Page 45: ...26 CHAPTER 2 NOTES ON HANDLING DEVICES ...
Page 83: ...64 CHAPTER 3 CPU ...
Page 95: ...76 CHAPTER 4 RESET ...
Page 107: ...88 CHAPTER 5 CLOCK ...
Page 131: ...112 CHAPTER 6 LOW POWER CONSUMPTION MODE ...
Page 175: ...156 CHAPTER 7 INTERRUPT ...
Page 181: ...162 CHAPTER 8 MODE SETTING ...
Page 223: ...204 CHAPTER 9 I O PORT ...
Page 237: ...218 CHAPTER 10 TIME BASE TIMER ...
Page 247: ...228 CHAPTER 11 WATCHDOG TIMER ...
Page 275: ...256 CHAPTER 12 16 BIT RELOAD TIMER ...
Page 373: ...354 CHAPTER 14 MULTI FUNCTIONAL TIMER ...
Page 485: ...466 CHAPTER 16 PWC Timer ...
Page 531: ...512 CHAPTER 17 UART ...
Page 559: ...540 CHAPTER 19 DELAYED INTERRUPT GENERATOR MODULE ...
Page 589: ...570 CHAPTER 20 8 10 BIT A D CONVERTER ...
Page 601: ...582 CHAPTER 21 ROM CORRECTION FUNCTION ...
Page 633: ...614 CHAPTER 23 512K 1024K BIT FLASH MEMORY ...
Page 645: ...626 CHAPTER 24 EXAMPLE OF F2 MC 16LX MB90F462 F462A F463A CONNECTION FOR SERIAL WRITING ...
Page 715: ...696 APPENDIX ...
Page 716: ...697 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 739: ......