DMA Instructions

There are ten DMA instructions.

Selector	Opcode	Description
0	DMA SAD	Store word register to DMA Address register
1	DMA RAD	Read word register from DMA Address register
2	DMA SCT	Store word register to DMA Count register
3	DMA RCT	Read word register from DMA Count register
4	DMA SDV	Set DMA device. Device is constant in register nibble
5	DMA RDV	Set DMA device. Device is read from register in register nibble. Will always use the low byte even if a high byte register is provided. Note that the assembler will only allow an even register (or register pair) as valid syntax. (note CPU5 this is Read Device)
6	DMA EAB	Enable DMA
7	DMA DAB	Disable DMA
8	DMA SMN	DMA Store Map Number. Load low three bits of Internal Status Register from register. Will always use the low byte even if a high byte register is provided. Note that the assembler will only allow an even register (or register pair) as valid syntax. CPU6 only
9	DMA RMN	DMA Read Map Number. Store Internal Status Register to register. This instruction is buggy and will only store some of the bits depending on the register provided (the status register is masked on the inverse of the register number). Best results will be with AH. Will always use the low byte even if a high byte register is provided. Note that the assembler will only allow an even register (or register pair) as valid syntax. CPU6 only.