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Rainbow Electronics AT89C5131 User Manual

Page 50

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50

AT89C5131

4136A–USB–03/03

Note:

1. These functions can only be called by user’s code. The standard bootloader cannot

decrease the security level.

READ BOOT STATUS BYTE

Input Parameters:

R0 = osc freq (integer Not required, left for Philips
compatibility)

R1 = 07h

DPH = 00h

DPL = 01h (status byte)

Return Parameter

ACC = value of byte read

READ BOOT VECTOR

Input Parameters:

R0 = osc freq (integer Not required, left for Philips
compatibility)

R1 = 07h

DPH = 00h

DPL = 02h (boot vector)

Return Parameter

ACC = value of byte read

FULL CHIP ERASE

Input Parameters:

R0 = osc freq (integer Not required, left for Philips
compatibility)

R1 = 08h

DPH = don’t care

DPL = don’t care

Return Parameter

none

Table 41. API Calls (Continued)

API Call

Parameter