7477 datasheet(41/48 Pages) RENESAS

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MITSUBISHI MICROCOMPUTERS

7477/ 7478 GROUP

SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

PROGRAMMING NOTES

(1) The frequency ratio of the timer is 1/(n+1).

(2) The contents of the interrupt request bits are not modified im-

mediately after they have been written. After writing to an

interrupt request register, execute at least one instruction be-

fore executing a BBC or BBS instruction.

(3) To calculate in decimal notation, set the decimal mode flag (D)

to “1”, then execute an ADC or SBC instruction. Only the ADC

and SBC instruction yield proper decimal results. After execut-

ing an ADC or SBC instruction, execute at least one

instruction before executing a SEC, CLC, or CLD instruction.

(4) An NOP instruction must be used after the execution of a PLP

instruction.

(5) Do not execute the STP instruction during A-D conversion.

(6) In the 7477 group, set bit 0, bit 1, and bit 3 – bit 7 to “0” of the

CPU mode register.

(7) Multiply/Divide instructions

The index X mode (T) and the decimal mode (D) flag do not

affect the MUL and DIV instruction.

The execution of these instructions does not modify the con-

tents of the processor status register.

DATA REQUIRED FOR MASK ORDERING

Please send the following data for mask orders.

(1) mask ROM confirmation form

(2) mark specification form

(3) ROM data ......................................................... EPROM 3 sets

7477 Datasheet(PDF) 41 Page - Renesas Technology Corp