SC65D02C40

3.3 P3 port

[Description]

P3 of SC65D02C40 has only one bit which is only as output port.

3.4 ROM

[Description]

SC65D02C40 has built-in 40K-byte read-only memory(ROM), and the address range is 6000H ~FFFFH. The

configuration area FFF0H~FFFFH contains reset and interrupt vectors for normal working mode and test

mode.shown in figure 5:

Figure 5 – MASK configuration area

The reset vector value is the initial value of PC after the circuit is reset, that is the entry address of the main

program, where, the high byte is stored in FFFBH, and low byte is stored in FFFAH. For example: FFFAH

stores 40H, FFFBH stores 80H, then after the circuit is reset, then PC points to 8040H.

The interrupt vector value is the initial value of PC after MCU responses to the interrupt, which is the entry

address of the interrupt service routine, where, the high byte is stored in FFF9H, and low byte is stored in

FFF8H. For example: FFF8H stores 00H, FFF9H stores 80H, then the interrupt entry address is 8000H.

The reset vector value and the interrupt vector value in test mode are useful in production test, and the

customer should set FFF0H with 00H, FFF1H with 60H, FFF2H with 04H, FFF3H with 60H to make sure the

program down load is correct, for example, the customer should add the following code in proper position:

ORG

FFF0H

DW

6000H

DW

6004H

HANGZHOU SILAN MICROELECTRONICS CO.,LTD

REV:1.1

2008.12.10

Http: //www.silan.com.cn

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