.. _pocketbeagle_change_history:

Change History
###############

This section describes the change history of this document and board.
Document changes are not always a result of a board change. A board
change will always result in a document change.

.. _document_change_history:

Document Change History
************************

.. table:: Change History

    +--------+--------------------------------------+--------------------+--------+
    |**Rev** | **Changes**                          | **Date**           | **By** |
    +========+======================================+====================+========+
    |A.x     | Production Document                  | *December 7, 2017* | JK     |
    +--------+--------------------------------------+--------------------+--------+
    |0.0.5   | Converted to .rst and gitlab hosting | *July 21, 2022*    | DK     |
    +--------+--------------------------------------+--------------------+--------+

.. _board_changes:

Board Changes
***************

.. table:: Board History  

    +---------+-----------------------------------------------------------------------------------------+----------------------+--------+
    | **Rev** | **Changes**                                                                             | **Date**             | **By** |
    +=========+=========================================================================================+======================+========+
    | A1      | Preliminary                                                                             | *February 14, 2017*  | JK     |
    +---------+-----------------------------------------------------------------------------------------+----------------------+--------+
    | A2      | Production. Fixed                                                                       | *September 22, 2017* | JK     |
    |         | mikroBUS Click reset                                                                    |                      |        |
    |         | pins (made GPIO).                                                                       |                      |        |
    +---------+-----------------------------------------------------------------------------------------+----------------------+--------+
    | A2a     | Fixed label on P2_24. Was labeled GPIO48, should be GPIO44.                             | *November 7, 2017*   | JK     |
    +---------+-----------------------------------------------------------------------------------------+----------------------+--------+
    | A2b     | Because there are 2 TI parts which have long lead-time,                                 | *June 15, 2021*      | JK     |
    |         | we made the following changes:                                                          |                      |        |
    |         |                                                                                         |                      |        |
    |         | 1. Use ESD discrete devices instead of integrated TVS TI: TPD4S012DRYR.                 |                      |        |
    |         | 2. Change Logic IC TI SN74LVC1G07DCKR to Nexperia 74LVC1G07GV                           |                      |        |
    +---------+-----------------------------------------------------------------------------------------+----------------------+--------+

PocketBone
**********

Upon the creation of the first, 27mm-by-27mm, Octavo Systems OSD3358
SIP, Jason did a hack two-layer board in EAGLE called “PocketBone” to
drop the Beagle name as this was a totally unofficial effort not geared
at being a BeagleBoard.org Foundation project. The board never worked
because the 32kHz and 24MHz crystals were backwards and Michael Welling
decided to pick it up and redo the design in KiCad as a four-layer
board. Jason paid for some prototypes and this resulted in the first
successful “PocketBone”, a fully-open-source 1-GHz Linux computer in a
fitting into a mini-mint tin.

.. _rev_a1:

Rev A1
======

The Rev A1 of PocketBeagle was a prototype not released to production. A
few lines were wrong to be able to control mikroBUS Click add-on board
reset lines and they were adjusted.

.. _rev_a2:

Rev A2
======

The Rev A2 of PocketBeagle was released to production and
`launched at World MakerFaire 2017 <https://www.prnewswire.com/news-releases/small-in-size--cost-meet-pocketbeagle-the-25-development-board-for-hobbyists-educators-and-professionals-300519950.html>`__.

Known issues in rev A2:

+----------------------------------+----------------------------------------------------------------------------------+
| **Issue**                        | **Link**                                                                         |
+==================================+==================================================================================+
| GPIO44 is incorrectly labelled   | `Issue #4 <https://git.beagleboard.org/beagleboard/pocketbeagle/-/issues/4>`__   |
| as GPIO48                        |                                                                                  |
+----------------------------------+----------------------------------------------------------------------------------+

Rev A2B
=======

Because 2 TI parts had a long lead time, we made the following changes:

+---------------+-------------------------------------------------+-----------------------+--------------+-----------------+-----------------------------+
| Change # | Modification                                         | Reference Designators | Part Type    | Before（value ）| After（value)               |
+==========+======================================================+=======================+==============+=================+=============================+
| 1        | Changed C2,C3 from 18pF to 22pF.                     | C2,C3                 | Cap Ceramic  | 18pF            | 22pF                        |
+----------+------------------------------------------------------+-----------------------+--------------+-----------------+-----------------------------+
| 2        | Changed Y1 from 24MHz_18pF to 24MHz_22pF.            | Y1                    | Crystal      | 24MHz_18pF      | 24MHz_22pF                  |
+----------+------------------------------------------------------+-----------------------+--------------+-----------------+-----------------------------+
| 3        | Use ESD discrete devices(D1-D4) to replace U3.       | U3                    | ESD Solution | integrated      | ESD discrete devices(D1-D4) |
+----------+------------------------------------------------------+-----------------------+--------------+-----------------+-----------------------------+
| 4        | Changed U2 from SN74LVC1G07DCKR to 74LVC1G07GV,125.  | U2                    | Logic        | SN74LVC1G07DCKR | 74LVC1G07GV,125             |
+----------+------------------------------------------------------+-----------------------+--------------+-----------------+-----------------------------+
| 5        | The PCB Revision for this board is Rev A2b.          | The PCB Revision for this board is Rev A2b.	                                         |
+----------+------------------------------------------------------+-----------------------+--------------+-----------------+-----------------------------+