
73
CHAPTER 3 INTERRUPTS
3.7.1
Extended Intelligent I/O Service Descriptor (ISD)
The extended intelligent I/O service descriptor exists between "000100
H
" and "00017F
H
"
in built-in RAM, and consists of the following items:
• Data transfer control data
• Status data
• Buffer address pointer
■
Extended Intelligent I/O Service Descriptor (ISD)
Figure 3.7-2 shows the configuration of the extended intelligent I/O service descriptor.
Figure 3.7-2 Extended Intelligent I/O Service Descriptor Configuration
■
Data Counter (DCT)
This is a 16-bit register that works as a counter corresponding to the number of data items transferred. This
counter is decremented by one before data transfer. EI
2
OS is terminated when this counter reaches "0".
Figure 3.7-3 is a diagram of the data counter configuration.
Figure 3.7-3 Data Counter Configuration
High-order 8 bits of data counter (DCTH)
Lo
w
-order 8 bits of data counter (DCTL)
High-order 8 bits of I/O address pointer (IOAH)
Lo
w
-order 8 bits of I/O address pointer (IOAL)
EI
2
OS status (ISCS)
High-order 8 bits of buffer address pointer (BAPH)
Medium-order 8 bits of buffer address pointer (BAPM)
Lo
w
-order 8 bits of buffer address pointer (BAPL)
"H"
"L"
ISD start address
000100
H
+ 8
×
ICS
B15 B14 B13 B12 B11 B10 B09 B08 B07 B06 B05 B04 B03 B02 B01 B00
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
bit
DCT
(Undefined
w
hen reset)
Summary of Contents for MB90390 Series
Page 2: ......
Page 4: ......
Page 17: ...xiii APPENDIX D List of Interrupt Vectors 690 INDEX 695 ...
Page 18: ...xiv ...
Page 132: ...104 CHAPTER 5 CLOCKS ...
Page 152: ...124 CHAPTER 6 CLOCK MODULATOR ...
Page 210: ...182 CHAPTER 11 TIME BASE TIMER ...
Page 218: ...190 CHAPTER 12 WATCHDOG TIMER ...
Page 264: ...236 CHAPTER 14 16 BIT RELOAD TIMER WITH EVENT COUNT FUNCTION ...
Page 274: ...246 CHAPTER 15 WATCH TIMER ...
Page 306: ...278 CHAPTER 17 DTP EXTERNAL INTERRUPTS ...
Page 338: ...310 CHAPTER 18 8 10 BIT A D CONVERTER ...
Page 364: ...336 CHAPTER 19 UART0 UART1 ...
Page 398: ...370 CHAPTER 20 UART2 UART3 Figure 20 5 2 ORE Set Timing Receive data RDRF ORE ...
Page 432: ...404 CHAPTER 20 UART2 UART3 ...
Page 482: ...454 CHAPTER 22 SERIAL I O ...
Page 560: ...532 CHAPTER 24 STEPPING MOTOR CONTROLLER ...
Page 582: ...554 CHAPTER 27 ROM MIRRORING MODULE ...
Page 632: ...604 CHAPTER 29 EXAMPLES OF SERIAL PROGRAMMING CONNECTION ...
Page 722: ...694 APPENDIX ...
Page 723: ...695 INDEX The index follows on the next page This is listed in alphabetic order ...
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