■4.5 Instruction details

◆Instruction list

◆Arithmetic instructions

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

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

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

Figure 4.5 Arithmetic instruction format

31	30	29				25					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 the mnemonic, write the ALU control command on the left end, and write any other necessary commands separated by spaces or tabs.

◆Load Immediate instruction

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. Details of the instructions will be shown from the next page.

Figure 4.6 Load Immediate command format 1 (unconditional transfer)

31	30	29			26	25	24																								0
1	0	Storage location				0	Immediate data

Figure 4.7 Load Immediate command format 2 (conditional transfer)

31	30	29			26	25	24					19	18																		0
1	0	Storage location				1	situation						Immediate data

◆DMA instruction

DMA instructions perform data transfers between external and DSP internal RAM via the external bus. There are two methods: directly setting the number of transfer words using Imm data, and setting 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. Details of the instructions will be shown from the next page.

Figure 4.8 DMA instruction format 1

31	30	29	28	27									18	17		15	14	13	12	11	10		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	10		8	7				3	2		0
1	1	0	0	−	−	−	−	−	−	−	−	−	−	addition mode			H	0	dir	−	RAM			−	−	−	−	−	SOURCE

◆JUMP instruction

The JUMP instruction is achieved by storing immediate data in the program counter. Figure 4.10 shows the format of the JUMP instruction. Details of the instructions will be shown from the next page.

Figure 4.10 JUMP instruction format

31	30	29	28	27	26	25						19	18										8	7							0
1	1	0	1	−	−	situation							−	−	−	−	−	−	−	−	−	−	−	Immediate

◆LOOP BOTTOM instruction

The LOOP BOTTOM instruction executes a program of one to several steps repeatedly. The format is shown in Figure 4.11. Details of the instructions will be 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 as shown in Figure 4.12. Details of the instructions will be shown from the next page.

Figure 4.12 END instruction format

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