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CHAPTER 17 UART
17.5
UART Interrupts
UART uses both reception and transmission interrupts. An interrupt request can be
generated for either of the receive data is set in the input register (SIDR0/SIDR1), or a
reception error occurs and transmission data is transferred from output data register 1
(SODR0/SODR1) to the transmission shift register.
The extended intelligent I-O service (EI
2
OS) is available for these interrupts.
■
UART Interrupts
Table 17.5-1 lists the interrupt control bits and causes of UART
●
Reception interrupt
If one of the following events occurs in reception mode, the corresponding flag bit of the status register is
set to "1":
•
Data reception is complete (SSR0/SSR1: RDRF)
•
Overrun error (SSR0/SSR1: ORE)
•
Framing error (SSR0/SSR1: FRE)
•
Parity error (SSR0/SSR1: PE)
When at least one of the flag bits is "1" and the reception interrupts are enabled (SSR0/SSR1: RIE = 1), a
reception interrupt request is output to the interrupt controller.
When the input data register (SIDR0/SIDR1) is read, the receive data full flag (SSR0/SSR1: RDRF) is
automatically cleared to "0". When "0" is written to the REC bit of the control register (SCR0/SCR1), all
the reception error flags (SSR0/SSR1: PE, ORE and FRE) are cleared to "0".
Table 17.5-1 Interrupt Control Bits and Interrupt Causes of UART
Reception/
transmission
Interrupt
request flag bit
Operation mode
Interrupt cause
Interrupt cause
enable bit
When interrupt request
flag is cleared
0
1
2
Reception
RDRF
O
O
O
Loading receive data
into buffers (SIDR0/
SIDR1)
SSR0/SSR1:RIE
Receive data is read
ORE
O
O
O
Overrun error
0 is written to the
reception error flag clear
bit (SSR0/SSR1: REC)
FRE
O
O
X
Framing error
PE
O
X
X
Parity error
Transmission
TDRE
O
O
O
Empty transmission
buffer (SODR0/
SODR1)
SSR0/SSR1:TIE
Transmission data is
written
O: Used
X: Not used
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: ......