sub_reset_lcd_controller.s

此为Microchip的试验程序

;START_HEADER
;
; dsPIC30F6014 Demo Source File
; (c) Copyright 2005 Microchip Technology, All rights reserved
;
; --------------------------------------------------------------------------
; File Revision History:
; --------------------------------------------------------------------------
;
; $Log: sub_reset_lcd_controller.s,v $
; Revision 1.1  2006/07/07 15:32:10  c13075
; initial rev
;
; Revision 1.3  2005/04/04 23:38:25  VasukiH
; Updated comments in header
;
; Revision 1.2  2005/04/04 23:13:54  VasukiH
; Updates for MPLAB C30 v1.30 compatiblity
;
; Revision 1.1.1.1  2003/08/23 00:38:33  VasukiH
; First import of demo source into CVS Repository
;
;
;
; --------------------------------------------------------------------------
;
; Software and Development Tools Info:
; --------------------------------------------------------------------------
; Tool                          Version
; --------------------------------------------------------------------------
; MPLAB IDE                     7.0
; MPLAB C30 Toolsuite           1.30
; dsPICDEM(TM) Processor Board  1.10
; --------------------------------------------------------------------------
;
; File Notes:
; 1. This subroutine will reset the LCD controller and provide a power-up
;    time delay so that the dsPIC does not communicate to the LCD controller
;    before the LCD controller has fully powered up. The time delay provided
;    is ~250milliseconds which should be more than enough to ensure the LCD
;    has power-up fully.
;
;END_HEADER

.include "p30fxxxx.inc"

.global _sub_reset_lcd_controller
_sub_reset_lcd_controller:

        push.d  w0

;Ensure LCD Controller is up and running
        mov     #256, w0
        mov     #7080, w1
        do      w1, end_delay1
        repeat  w0
        nop
        nop
end_delay1:
        nop

;Reset LCD Controller
        bclr    SPI2STAT, #SPIROV               ;Clear overflow flag
        bset    LATG, #LATG9                    ;Deselect Slave LCD controller
        bclr    LATG, #LATG9                    ;Select Slave LCD controller

        mov.b   SPI2BUF, WREG
        mov.b   #0x80, w0
        mov.b   WREG, SPI2BUF
poll_port:
        btss    SPI2STAT, #SPIRBF
        bra     poll_port
        mov.b   SPI2BUF, WREG

;Ensure LCD Controller is up and running again
        mov     #256, w0
        mov     #7080, w1
        do      w1, end_delay2
        repeat  w0
        nop
        nop
end_delay2:
        nop


;Enable SPI Interrupt Processing
        bset    IEC1, #SPI2IE                   ; Enable SPI2 ISR processing

        pop.d   w0
        return


.end                                            ;EOF