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OTP Module API Manual

Overview

CanMV K230 provides the OTP (One-Time Programmable) class for reading chip OTP data and querying the read/write lock status of a specified address.

The OTP object is a singleton object, and repeated calls to OTP() return the same instance.

API Introduction

The OTP class is located under the machine module.

Example

from machine import OTP
import binascii

otp = OTP()

data = otp.read(0x000, 32)
print(binascii.hexlify(data))

lock = otp.get_lock(0x000)
if lock == OTP.NA:
    print("No Access")
elif lock == OTP.RO:
    print("Read Only")
elif lock == OTP.RW:
    print("Read Write")

Constructor

otp = OTP()

Parameters

None

Return Value

Returns the OTP singleton object.

read Method

data = otp.read(addr, length)

Function

Reads byte data from the specified address in OTP.

Parameters

• addr: The starting address to read from, ranging from 0x000 to 0xFFF, must be 4-byte aligned.

• length: The read length, ranging from 1 to 1024 bytes.

Return Value

Returns the read OTP data, of type bytes.

Restrictions

• addr + length cannot exceed the total OTP range.

• A single read cannot cross the 0x400 boundary.

get_lock Method

lock = otp.get_lock(addr)

Function

Query the read/write lock status of the specified OTP address.

Parameters

• addr: The OTP address to query, ranging from 0x000 to 0xFFF, must be 4-byte aligned.

Return Value

Returns a lock status integer, which can be compared with the following constants:

Constant	Value	Description
OTP.NA	0	No Access
OTP.RO	1	Read Only
OTP.RW	2	Read Write

Constants

Constant	Description
OTP.NA	OTP address is not accessible
OTP.RO	OTP address is read-only
OTP.RW	OTP address is readable and writable

Notes

• OTP may store device security configuration or identity-related information. Please confirm the usage scenario before printing or saving.

• Currently, machine.OTP only provides read and lock status query interfaces, and does not provide write or lock interfaces.