DS2505

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HIERARCHICAL STRUCTURE FOR 1-WIRE PROTOCOL Figure 2

64-BIT LASERED ROM Figure 3

8-Bit CRC Code

48-Bit Serial Number

8-Bit Family Code (0BH)

MSB

LSB MSB

LSB MSB

LSB

16384-BITS EPROM

The memory map in Figure 4 shows the 16384-bit EPROM section of the DS2505 which is configured as

64 pages of 32 bytes each. The 8-bit scratchpad is an additional register that acts as a buffer when

programming the memory. Data is first written to the scratchpad and then verified by reading a 16-bit

CRC from the DS2505 that confirms proper receipt of the data and address. If the buffer contents are

correct, a programming voltage should be applied and the byte of data will be written into the selected

address in memory. This process ensures data integrity when programming the memory. The details for

reading and programming the 16384-bit EPROM portion of the DS2505 are given in the Memory

Function Commands section.