A fast and easily customised operating system for ARM devices

Poll Mask

Bit	Meaning when set
0	Do not return Null_Reason
1	Do not return Redraw_Window_Request. Queue it
2	Must be 0
3	Must be 0
4	Do not return Pointer_Leaving_Window
5	Do not return Pointer_Entering_Window
6	Do not return Mouse_Click. Queue it
7	Must be 0
8	Do not return Key_Pressed. Queue it
9	Must be 0
10	Must be 0
11	Do not return Lose_Caret
12	Do not return Gain_Caret
13	Do not return PollWord non-zero?
14	Must be 0
15	Must be 0
16	Must be 0
17	Do not return User_Message
18	Do not return User_Message_Recorded
19	Do not return User_Message_Acknowledge
20	Must be 0
21	Must be 0
22	R3 is pointer to PollWord
23	Scan PollWord at high priority
24	Save Floating Pointer Registers
25	Must be 0
26	Must be 0
27	Must be 0
28	Must be 0
29	Must be 0
30	Must be 0
31	Must be 0

For commercial enquiries, please contact the owners of RISC OS, Castle Technology Ltd.