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%X; Parallel Device Handler ExampleX; By Earl RiceX; ANTIC Magazine(X;25X;(ASM,,#D:MYFILE.OBJ) because the obj code is put<%X;where there is no RAM available.FFPX;  EQUATESZ9�PDVMSKG;;Parallel device mask (indicates which ared9�PDIMSKI;;Parallel interrupt mask (not used in thisn-�GPDVV��;;Generic Parallel Device VectorxX;�$�HATABS;;Device handler table�)�CRITICB;;Critical code section flag�X;�3�DEVNAM
T;;Device name, E.G. T for "Telephone".�$�HWGET�;;Hardware GET register�%�HWPUT�;;Hardware PUT register.�5�HWRSET
�;;Hardware reset (clears get register).�)�HWSTAT
�;;Hardware STATUS register.�X;���X; Rom vector table�	;;Optional ROM checksum� ;;Optional Revision number
�;;Mandatory ID number
;;Optional Name or Type
4!�NONEED;;Lo-level IO vector, which we don't need"
5!�NONEED;;IRQ handler vector, which we don't need.,
�;;Mandatory ID number6
�DEVNAM;;Device name@
1	�NONEED
;;Open vector, which we don't need.J
2	�NONEED
;;CLOSE vector, which we don't need.T
 	�GETBYT
;;GET BYTE vector.^
 	�PUTBYT
;;PUT BYTE vector.h
"	�GETSTA
;;GET STATUS vector.r
4	�NONEED
;;SPECIAL vector, which we don't need.|
,!�INIT;;INIT vector at power up or reset.�
;;NOT USED.�
X;�
X;CODE STARTS HERE�
X;�
)X;Initialize device and device handler�
�INIT�
%Q�PDVMSK;;Get enabled device flags�
L>
;;Set bit 0.�
P�PDVMSK;;& replace.�
:X;Note: if device used interrupts we would set bit 0 of�
X;�
,X;Put device name in Handler table HATABS�
$>X;        Top of loop
�SEARCH#Q�HATABS9;;Get a byte from table&#F�FNDIT;;0? Then we found space.02:2D2N(>$;;Length of HATABSXD�SEARCH;;Still lookingb/:;;No room in HATABS; device not initializedlX;vX;         We found a spot.�	�FNDIT�Q>�DEVNAM;;Get device name.�#P�HATABS9;;Put it in blank spot.�2�&Q>�GPDVV�;;Get lo byte of vector.�'Q>�GPDVV
;;Get hi byte of vector.�P�HATABS9�:�X;�X; GET BYTE routine.�
�GETBYT�Q>�-P�CRITIC;;Enable deferred  vertical blank.%Q�HWGET;;Get a byte from hardware.P�HWRSET;;Reset hardware.;;;Indicate we handled it. :*X;4X; PUT BYTE routine.>
�PUTBYTH$>R-&�CRITIC;;Enable deferred  vertical blank.\!P�HWPUT;;Put byte to hardware.f;;;Indicate we handled it.p:zX;�X; GET STATUS routine.�
�GETSTA�Q>�-P�CRITIC;;Enable deferred  vertical blank.�Q�HWSTAT;;Get HW status.�;;;Indicate we handled it.�:�X;�X; Do nothing routine.�
�NONEED�;;;Indicate we handled it.�:�X;X;

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