DS2505 - Add-Only Memory (16 kBit), UniqueWare Add-Only Memory (16 kBit)

NAME SYNOPSIS FAMILY CODE SPECIAL PROPERTIES memory pages/page.0 ... pages/page.63 pages/page.ALL STANDARD PROPERTIES ALARMS DESCRIPTION DS2505 DS1985 ADDRESSING DATASHEET SEE ALSO AVAILABILITY AUTHOR

NAME

DS2505, DS2505-UNW − Add-Only Memory (16 kBit), UniqueWare Add-Only Memory (16 kBit)
DS1985, DS1985U

− Add-Only iButton (16 kBit), UniqueWare iButton (16 kBit)

SYNOPSIS

EPROM add-only memory.

0B [.]XXXXXXXXXXXX[XX][/[ memory | pages/page.[0-63|ALL] | ]]

8B [.]XXXXXXXXXXXX[XX][/[ memory | pages/page.[0-63|ALL] | ]]

FAMILY CODE

	0B		DS2505 DS1985
	8B		DS2505-UNW DS1985U

SPECIAL PROPERTIES

memory

read-write, binary
2048 bytes of memory. Initially all bits are set to 1. Writing zero permanently alters the memory.

pages/page.0 ... pages/page.63 pages/page.ALL

read-write, yes-no
Memory is split into 64 pages of 32 bytes each. ALL is an aggregate of the pages. Each page is accessed sequentially.

DESCRIPTION

DS2505 DS1985

The DS2505 (3) is used for write-once incremental storage. It’s main advantage is for audit trails (i.e. a digital purse).

The DS2505-UNW is one of the UniqueWare class of devices. Some of the memory was preprogramed at the factory. See the datasheet for specifics. The DS2502 , DS2505 , and DS2506 differ in their function by the amount of on-board memory they possess. (The internal protocols are slightly different, but the OWFS system handles this automatically.