NEC µPD72257 Preliminary User's Manual page 263

Drawing Engine
8.9.2.5
Access
Address
Index
Initial Value
Bit Bit name
6 BUSIRQ
5 DLISTIRQ
4 ENUMIRQ
3 DLISTACTIVE
2 CACHEDIRTY
1 BUSYWRITE
0 BUSYENUM
DRWSTATUS - Status control register
The current Drawing Engine status can be polled by reading this register.
This register can be read in 32-bit units.
<DrwE_Base> + 00
H
no index because of read only access
0000 0000 . This register is initialized by any reset.
H
31 30
0 0
R R
23 22
0 0
R R
15 14
0 0
R R
7 6
DLISTIR
0 BUSIRQ
R R
Function
0 no bus error occurred or interrupt disabled
1 bus error interrupt triggered
0 display list not finished or interrupt disabled
1 display list finished interrupt triggered
0 enumeration not finished or interrupt disabled
1 enumeration finished interrupt triggered
0 display list reader is idle
1 display list reader busy, no direct access to registers
0 framebuffer cache is not dirty
1 framebuffer cache is dirty, frame should not be flipped
0 framebuffer writeback finished
1 framebuffer writeback busy, framebuffer type can not be changed
0 enumeration unit idle
1 enumeration unit busy, new primitive can not be started
Preliminary User's Manual S19203EE1V3UM00
29 28 27
0 0 0
R R R
21 20 19
0 0 0
R R R
13 12 11
0 0 0
R R R
5 4 3
ENUMIR DLIST
Q Q ACTIVE
R R R
Chapter 8
26 25 24
0 0
R R
18 17 16
0 0
R R
10 9
0 0
R R
2 1
CACHED BUSYWR BUSYEN
IRTY ITE UM
R R
0
R
0
R
8
0
R
0
R
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