MC68000 MOTOROLA [Motorola, Inc], MC68000 Datasheet - Page 363

• Manufacturer Part Number: MC68000
• Manufacturer: MOTOROLA [Motorola, Inc]

MOTOROLA
* Set up PACNT, PBCNT, etc., ignore for this example, only SCC1 is used
* Select Serial Interface Mode: normal operation, NMSI mode
*** SCC1 Initialization ***
*
*
* Determine Configuration
* Use Baud Rate Generator for transmit and receive, Rate is 130 kbps.
* Select SCC Mode
* HDLC, Loopback mode, CRC16, RTS negate between frames, NRZ mode.
* Set up Parameter RAM
* Clear Event Register
* Determine Maskable Interrupt Events by setting SCCM
* Allow the following interrupt: TXE, RFX, TXB, and RFB
* Clear M68000 data registers
***Prepare Buffer Descriptors ***
*SCC1 Rx Buffer Descriptors Initialization values before execution:
*00700400 D000 0000 0003 0000 D000 0000 0003 0010
*00700410 D000 0000 0003 0020 D000 0000 0003 0030
*00700420 D000 0000 0003 0040 D000 0000 0003 0050
*00700430 D000 0000 0003 0060 F000 0000 0003 0070
*
v7–v5 =5, v4–v0 = $ad -> vector = $ad -> Exception vector = ($ad<<2) = $2b4
Interrupt Vector: SCC1 interrupt handler is at INT_VEC = $31000
MOVE.W
MOVE.L
MOVE.W
MOVE.W
MOVE.W
MOVE.W
MOVE.W
MOVE.W
MOVE.W
MOVE.W
MOVE.W
MOVE.W
MOVE.W
MOVE.W
MOVE.B
MOVE.B
CLR.L
CLR.L
CLR.L
CLR.L
CLR.L
CLR.L
LEA.L
LEA.L
MOVE.W
MOVE.W
#0,SIMODE
#INT_VEC, $02B4
#$07E,SCON1
#$10,SCM1
#0,FCR_1
#$08,MRBLR_1
#$F0B8,CMSKL_1
#$070,MFLR_1
#0,HMASK_1
#0,DISFC_1
#0,CRCEC_1
#0,ABTSC 1
#0,NMARC_1
#0,RETRC_1
#$FF,SCCE1
#$1B,SCCM1
D0
D1
D2
D3
D4
D5
RXBD_01,A0
RXBF_01,A1
#$D000,D1
#$F000,D2
MC68302 USER’S MANUAL
;Same as default after reset
; Clear RFCR and TFCR
; Max Buffer Length = 8
; 16 bit CRC
; Max Frame Length = $70 bytes
; Do not check address
; Clear the counter
; Clear the counter
; Clear the counter
; Clear the counter
; Clear the counter
;A0 points to the first RXBD of SCC1
;A1 points to the first buffer
;D1 is used for setting the status of BD
;Empty = 1, External = 1, Int=1
;D2 is for the last BD, Wrap = 1
MC68302 Applications
D-13