#  =========== Header ===========
#  File:				Newton Stores Collection Format
#  Project:				ATA Support for Newton OS
#  Written by:			Paul Guyot (pguyot@kallisys.net)
# 
#  Created on:			07/06/2000
#  Internal version:	1
# 
#  Copyright:			© 2000-2003 by Paul Guyot.
#  						All rights reserved worldwide.
#  ===========

#  =========== Change History ===========
#  07/14/2003	v3	[PG]	Update to version 3
#  09/27/2000	v2	[PG]	Modification of the introduction
#  07/06/2000	v1	[PG]	Creation of the file
#  ===========

Abstract
========

This document describes how to have several stores in a single segment of sectors.

Introduction
============

The NewtonStore collection allows to define several stores within the same drive or the same volume.
The interest is to use less sectors to declare those stores, and to put store flags in the collection.
It is a good idea to partition a big drive with NewtonOS, so that a whole store could be deactivated/used
as a backup space.

Partition Map description
=========================

Each store collection is made of a partition map (or stores map), which is one-several sectors, and stores.

All the data is stuffed as big endian, i.e. without any conversion from the Newton
(except the PCMCIA conversion, of course).

ULong are 32 bits unsigned words
UShort are 16 bits unsigned words
UChar are 8 bits unsigned words

Partition map description
Each sector in the partition map has the same format:

First 32 bytes: the header of each partition map sector:
ULong	signature									should be 'Newt' (4E657774)
ULong	format version								should be 00000003
ULong	number of sectors of the partition map		should be at least 00000001
ULong	index of this sector						should be at least 00000001
ULong	total number of entries
UShort	number of entries in this sector
UShort	reserved
ULong	reserved
ULong	reserved

The following 480 bytes are used as an array of 30 Newton Stores entries
Only the first entries depending on the field "number of entries in this sector" should be used.
[Note: I think I relaxed this constraint now, every entries are read, just do as I do: read all entries, but when you write the partition, avoid holes, write all entries at the beginning.]

UShort	type								should be 0001. 0000 means no entry
UShort	flags
Current Supported flags are:
	0001:	auto mount						the store is mounted when the card is inserted
	0002:	read only						the store is marked as read only
ULong	start sector						LBA, relative to the first stores map sector (i.e. absolute if the stores collection starts at sector 0)
ULong	size								size in sectors
ULong	reserved							should be 00000000

[Note: I don't recall, but apparently, I didn't implement the addition to the start sector (I have to check anyway), but currently, all the Newton Stores Collection start at sector 0, i.e. I don't have hybrid cards with DOS partitions and Newton Stores]

Implementation remarks
======================
We can imagine less than 30 stores described in a partition map sector with a following sector with less than 30 stores, too.
There can be several NewtonStoreCollections within a single drive, one per partition with a foreign partition map format.

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