Graphic Operation Queue Load - IBM RT Series Hardware Reference Manual

TNL SN20-9844 (March 1987) to 75X0235
Graphic Operation Queue Load
0
The queue load data example shown for each graphic operation type demonstrates what a queue
load might look like for that operation. For instance, to draw a line in BAMDA from the
decimal coordinates (X1,Y1
=
100,200) to (X2,Y2
=
512,384) with all pels on the line set to
1, you could use the graphic operation type X'35' (Vector Draw) with the following queue load
data.
System Addr. Queue Load
(low 24 bits) Data
X'D9F7FE' X'1064'
X'D9F7FC' X'00C8'
X'D9F7FA' X'5200'
X'D9F7F8' X'6180'
X'D9F7F6' X'DB5F'
1/0 DATA FIELD
7 8
Parameter
Name/Decimal Value
Xl / 100
Y1 / 200
X2 / 512
Y2 / 384
Execute Vector Draw subtype F
(Replace On) with dec Q flag on
15
GRAPHIC OP EXECUTE COMMAND WORD
FOR THIS EXAMPLE:
1 1 0 1 1 0 1 1 1 0 1 0 1 1 1 1 1
•
I I I I I I I I I I I I I I
(X'DB5F')
I I
--
I
I
II
Bits 00-03 EXECUTE DECODE
( 1 1 0 1 )
Bit 04 DECREMENT QUEUE COUNTER FLAG (ON)
Bit 05 GRAPHIC OP INTERRUPT FLAG (OFF)
Bits 06-11 GRAPHIC OP TYPE (X'35')
Bits 12-15 GRAPHIC OP LOGIC FUNCTION (subtype) (X'F')
To execute the graphic operation, write the queue pointer register with the queue pointer value
corresponding to the queue load starting address (X'FBFF' corresponds to X'D9F7FE') and then
increment the queue counter. Do a I/O memory write X'FBFF' to I/O channel memory address
X'D9F806' (queue pointer register location) and then a write to I/O address X'OD14' (increment
queue counter). The complete operation to write the queue load and execute it requires a total
of six memory write operations and one I/O write.
60 Extended Monochrome Graphics Adapter