Tandy 1000 HX Technical Reference Manual page 59

. TANDY COMPUTER PRODUCTS
54
0081
Address
Bit
Bit
Bit
Bit
Bit
Bit
Bit
Bit 7
0082
0
1
2
3
4
5
6
Address
Bit
Bit
Bit
Bit
Bit
Bit
Bit
Bit
0083
0
1
2
3
4
5
6
7
Address
Bit
Bit
Bit
Bit
Bit
Bit
Bit
Bit
0
1
2
3
4
5
6
7
0084-008F
00A0-00A7
Bit
0
1
2
3
4
5
6
7
WRITE ONLY
Description
DMA Ch 2 Address A16
DMA Ch 2 Address A17
DMA Ch 2 Address A18
DMA Ch 2 Address A19
Not Used
Not Used
Not Used
Not Used
WRITE ONLY
Description
DMA Ch 3 Address A16
DMA Ch 3 Address A17
DMA Ch 3 Address Al8
DMA Ch 3 Address A19
Not Used
Not Used
Not Used
Not Used
WRITE ONLY
Description
DMA Ch 0 - 1 Address A16
DMA Ch 0 - 1 Address A17
DMA Ch 0 - 1 Address A18
DMA Ch 0 - 1 Address A19
Not Used
Not Used
Not Used
Not Used
Not Used
NMI Mask Register, Write only
Description
External Video
0 = Normal Operation
1 = All Video Addresses
and Ports are Disabled
MEMCONFIG 1 - A17 128K SW
MEMCONFIG 2 - A18 256K SW
MEMCONFIG 3 - A19 512K SW
"1" Enable 256K of Video RAM
Not Used
Not Used
1 = Enable NMI
0 = Disabled