H8S2245 datasheet(669/818 Pages) RENESAS

669 / 818 page

Appendix A Instruction Set

Rev.3.00 Mar. 26, 2007 Page 627 of 772

REJ09B0355-0300

A.3

Number of States Required for Instruction Execution

The tables in this section can be used to calculate the number of states required for instruction

execution by the H8S/2000 CPU. Table A.4 indicates the number of instruction fetch, data

read/write, and other cycles occurring in each instruction. Table A.3 indicates the number of states

required for each cycle, depending on its size. The number of states required for execution of an

instruction can be calculated from these two tables as follows:

Execution states = I

× S

I + J × SJ + K × SK + L × SL + M × SM + N × SN

Examples: Advanced mode, program code and stack located in external memory, on-chip

supporting modules accessed in two states with 8-bit bus width, external devices accessed in three

states with one wait state and 16-bit bus width.

1. BSET #0, @FFFFC7:8

From table A.4:

I = L = 2,

J = K = M = N = 0

From table A.3:

I = 4,

L = 2

Number of states required for execution = 2

× 4 + 2 × 2 = 12

2. JSR @@30

From table A.4:

I = J = K = 2,

L = M = N = 0

From table A.3:

I = SJ = SK = 4

Number of states required for execution = 2

× 4 + 2 × 4 + 2 × 4 = 24

H8S2245 Datasheet(PDF) 669 Page - Renesas Technology Corp