1 / 23

The Serial Communication Interface (SCI) MC9S12-C32

The Serial Communication Interface (SCI) MC9S12-C32. Lecture L4.9. Reference. HCS12 Serial Communications Interface (SCI) Block Guide V02.08. S12SCIV2.pdf. PIM_9C32 Block Diagram. SCI module. SCI. Asynchronous Serial I/O The 68HCS12 SCI Interface Programming the SCI

philana-candice
Download Presentation

The Serial Communication Interface (SCI) MC9S12-C32

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Serial Communication Interface (SCI)MC9S12-C32 Lecture L4.9

  2. Reference HCS12 Serial Communications Interface (SCI) Block Guide V02.08 S12SCIV2.pdf

  3. PIM_9C32 Block Diagram SCI module

  4. SCI • Asynchronous Serial I/O • The 68HCS12 SCI Interface • Programming the SCI • SCI Interface Using Interrupts

  5. SCI • Asynchronous Serial I/O • The 68HCS12 SCI Interface • Programming the SCI • SCI Interface Using Interrupts

  6. SCI • Asynchronous Serial I/O • The 68HCS12 SCI Interface • Programming the SCI • SCI Interface Using Interrupts

  7. sci.asm ; SCI0 SC0BDH EQU $C8 ;baud rate control SC0CR1 EQU $CA ;SCI control reg 1 SC0CR2 EQU $CB ;SCI control reg 2 SC0SR1 EQU $CC ;SCI status reg SC0DRL EQU $CF ;SCI data reg RDRF EQU $20 ;SCSR mask ; INITIALIZE SCI sci0_init CLR SC0CR1 ;8 bit LDD #52 STD SC0BDH ;9600 baud LDAA #$0C STAA SC0CR2 ;enable tx & rx RTS

  8. ; INPUT BYTE FROM SERIAL PORT INTO A INCHAR LDAA SC0SR1 ;check status ANDA #RDRF ;check rdrf BEQ INCHAR ;wait for char LDAA SC0DRL ;get char in A RTS ; OUTPUT BYTE IN A TO SERIAL PORT OUTPUT TST SC0SR1 BPL OUTPUT ;loop until tdre STAA SC0DRL ;send A RTS

  9. Communicating with a PC

  10. sciecho.asm ; echo char to PC org $4000 sci_echo bsr sci0_init se1 bsr inchar bsr output bra se1 #include sci.asm

  11. SCI • Asynchronous Serial I/O • The 68HCS12 SCI Interface • Programming the SCI • SCI Interface Using Interrupts

  12. ; SCI Interface using interrupts File: SCIINT.WHP ; display characters from PC keyboard on LCD display SC0BDH EQU $C8 ;baud rate control SC0CR1 EQU $CA ;SCI control reg 1 SC0CR2 EQU $CB ;SCI control reg 2 SC0SR1 EQU $CC ;SCI status reg SC0DRL EQU $CF ;SCI data reg RDRF EQU $20 ;SCSR mask SCI0.IVEC EQU $0FD8 ;SCI0 user vector address + 2 ORG $4000 main jsr spi_init ;initialize spi jsr lcd_init ;initialize lcd jsr initq ;initialize queue jsr sci0_init ;initialize sci mn1 jsr checkq ;if queue is empty bcs mn1 ; wait jsr data8 ;store char on LCD ldy #3 jsr ms_delay ;delay ~10 ms bra mn1

  13. ; INITIALIZE SCI sci0_init SEI ;disable interrupts CLR SC0CR1 ;8 bit LDD #52 STD SC0BDH ;9600 baud LDAA #$2C STAA SC0CR2 ;enable tx & rx, RX INT LDD #SCI_INTSER STD SCI0.IVEC ;set sci int vector CLI ;enable interrupts RTS

  14. ; Interrupt service routine: get char and store in queue  SCI_INTSER LDAA SC0SR1 ANDA #RDRF BEQ SI1 ;if RDRF set LDAA SC0DRL ;read data (clears RDRF flag) JSR QSTORE ;and store it in queue SI1 RTI #INCLUDE QUEUE.ASM #INCLUDE LCD.ASM

More Related