Gateway ALR 8300 I/O Map, at each address location, The following table gives descriptions of what the memory is used for

I/O Map

The following table gives descriptions of what the memory is used forat each address location.

Address	Size	Description
(hex)
0000–000F	16 bytes	DMA-1
0020–0021	2 bytes	INT-1
0040	1 byte	Programmable interval timer 1
0041	1 byte	Refresh request counter 1
0042	1 byte	Speaker tone counter 2
0043	1 byte	Command mode register
0048	1 byte	Programmable interval timer 2
0049	1 byte	Reserved
004A	1 byte	CPU speed control counter 2
004B	1 byte	Command mode register
0061-0070	16 bytes	NMI status/registers
0080-008F	16 bytes	DMA page registers
00A0-00A1	2 bytes	INT-2
00C0-00DE	31 bytes	DMA2
0400-040F	16 bytes	DMA1
0461-0464	4 bytes	Extended NMI control
0480-048F	16 bytes	DMA high page register
04C2	1 byte	Reserved
04C6-04CE	8 bytes	DMA2
04D0-04DF	16 bytes	INT/DMA2
04E0-04FF	32 bytes	DMA

98 Maintaining and Troubleshooting the Gateway ALR 8300 Server