■ 4.5 Instruction details

◆ Instruction list

◆ Arithmetic instructions

Arithmetic instructions use the X, Y, and D1 buses and the Arithmetic Logic Unit (ALU). Arithmetic instructions can be classified into the following four types of control.

1. ALU control command
2. X-Bus control command
3. Y-Bus control command
4. D1-Bus control command

The format of the operation instruction is shown in Figure 4.5.

Figure 4.5 Arithmetic instruction format

31	30	29				twenty five					20	19					14	13													0
0	0	ALU control				X-Bus control						Y-Bus control						D1-Bus control

Arithmetic instructions can execute the above four types of instructions in parallel. For mnemonics, write the ALU control command at the left end, and separate the other required commands with spaces or tabs.

◆ Load Immediate command

The Load Immediate instruction transfers immediate data to the storage destination. Unconditional transfers follow the format shown in Figure 4.6, and conditional transfers follow the format shown in Figure 4.7. The details of the instruction are shown from the next page.

Figure 4.6 Load Immediate instruction format 1 (unconditional transfer)

31	30	29			26	twenty five	twenty four																								0
1	0	Storage destination				0	Immediate data

Figure 4.7 Load Immediate instruction format 2 (conditional transfer)

31	30	29			26	twenty five	twenty four					19	18																		0
1	0	Storage destination				1	Status						Immediate data

◆ DMA instruction

The DMA instruction executes data transfer between the outside and the DSP internal RAM via the external bus. There are two methods, one is to set the number of transfer words directly with Imm data, and the other is to set the number of transfer words in RAM by specifying the internal data RAM number. The former format is shown in Figure 4.8 and the latter in Figure 4.9. The details of the instruction are shown from the next page.

Figure 4.8 DMA instruction format 1

31	30	29	28	27									18	17		15	14	13	12	11	Ten		8	7							0
1	1	0	0	−	−	−	−	−	−	−	−	−	−	Addition mode			H	0	dir	−	RAM			Immediate

Figure 4.9 DMA instruction format 2

31	30	29	28	27									18	17		15	14	13	12	11	Ten		8	7				3	2		0
1	1	0	0	−	−	−	−	−	−	−	−	−	−	Addition mode			H	0	dir	−	RAM			−	−	−	−	−	SOURCE

◆ JUMP instruction

The JUMP instruction is realized by storing the immediate data in the program counter. Figure 4.10 shows the format of the JUMP instruction. The details of the instruction are shown from the next page.

Figure 4.10 JUMP instruction format

31	30	29	28	27	26	twenty five						19	18										8	7							0
1	1	0	1	−	−	Status							−	−	−	−	−	−	−	−	−	−	−	Immediate

◆ LOOP BOTTOM command

The LOOP BOTTOM instruction repeatedly executes a program in one to several steps. The format is shown in Figure 4.11. The details of the instruction are shown from the next page.

Figure 4.11 LOOP BOTTOM instruction format

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◆ END command

The END instruction terminates the currently running program. The format is shown in Figure 4.12. The details of the instruction are shown from the next page.

Figure 4.12 END instruction format

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