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PB286 And IS/VT286 Motherboard Layout

NOTE: The PB286 has 2 motherboard revisions, the IS/VT286 is the old motherboard.

1a. LAYOUT: NEW MOTHERBOARD

旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켠컴켠컴컴컴컴컴컴컴컴컴컴컴�
�                                           J1 聃컴1/2  旼컴커              �
�                                                 旼커읕컴켸     旼�      �
� 旼�  旼�  旼�  旼�  旼�  旼�  旼�  旼� 旼왯커   쿞 �    旼�    � �      �
� 남�  남�  남�  남�  남�  남�  남�  남� � 납 쿕� 쿥 �    � �    � �      �
� 남�  남�  남�  남�  남�  남�  남�  남� � 납 �2� �1 �    � �    읕�      �
� 남�  남�  남�  남�  남�  남�  남�  남� 읕牡켸   �  �    읕� 볏       旼엿
� 남�  남�  남�  남�  남�  남�  남�  남�          읕켸旼� 旼� 볏       � 납
� 남�  남�  남�  남�  남�  남�  남�  남� 旼�  旼� 旼� � � � � 볏 旼왯커� 납
� 남�  남�  남�  남�  남�  남�  남�  남� � �  � � � � � � � � 볏 � 납 냅켸�
� 남�  남�  남�  남�  남�  남�  남�  남� � �  � � � � 읕� 읕� 볏 � 납 넬커�
� 남�  남�  남�  남�  남�  남�  남�  남� 읕�  읕� 읕�         볏 읕牡켸� 납
� 남�  남�  남�  남�  남�  남�  남�  남�                      볏       � 납
� 남�  남�  남�  남�  남�  남�  남�  남� 旼� �袴敲旼� 旼컴�            읕冒
� 남�  남�  남�  남�  남�  남�  남�  남� � � �   볐 � �   �      旼왯커旼엿
� 남�  남�  남�  남�  남�  남�  남�  남� � � �   볐 � �   � 旼컴엿 납 납 납
� 남�  남�  남�  남�  남�  남�  남�  남� 읕� � U 봉켸 � U � �   납 납 납 납
� 읕�  쳐�  쳐�  쳐�  읕�  읕�  쳐�  쳐�     � 9 �    � 8 � � U 냅켸읕牡켸�
�      남�  남�  남�            남�  남� 旼� � 9 붚커 � 1 � � 6 넬커旼왯커�
�      남�  남�  남�            남�  남� � � �   볐 � �   � � 8 납 납 납 납
�      남�  남�  남�            남�  남� � � �   볐 � �   � �   납 납 납 납
�      남�  남�  남�            남�  남� 읕� 훤袴1/4읕� 읕컴� 읕컴牡켸읕牡켸�
�      남�  남�  남�            남�  남�          旼� 旼� 旼�    旼왯커旼엿
�      남�  남�  남� 旼�        남�  남�          쿚� 쿚� � �    � 납 납 납
�      읕�  읕�  읕� � �        읕�  읕� 旼컴컴커 쿞� 쿞� � �    � 납 납 납
�                    읕�                 �      � �4� �3� 읕�    읕牡켸읕冒
�       旼왯커旼�    旼� 旼컴왯컴커      � U110 � 읕� 읕� 旼왯커          �
�       � 납 납 넬커 쿞� �   납   �      �      � 旼� 旼� 쿚납O� 旼왯커   �
�       � 납 납 납 � 쿥� � U 납 U �      �      � � � � � 쿞납S� � 납 넬커�
�       � 납 납 납 � �2� � 1 납 1 �      읕컴컴켸 � � � � �2납1� � 납 납 납
�       읕牡켸읕牡켸 읕� � 2 납 2 �  旼왯커旼왯커 읕� 읕� 읕牡켸 읕牡켸� 납
�  旼컴왯컴커旼컴왯컴커  � 5 납 2 �  � 납 납 납 �                      읕冒
�  �   납   납   납   �  �   납   �  � 납 납 납 넬컴커旼컴왯커旼왯커旼왯커�
�  � U 납 U 납 U 납 U �  읕컴牡컴켸  � 납 납 납 납   납   납 납 납 납 납 납
�  � 1 납 1 납 1 납 1 � 旼�          읕牡켸읕牡켸� U 납 U 납 납 납 납 납 납
�  � 3 납 3 납 3 납 2 � � � 旼� 旼�  旼왯커旼왯커� 9 납 8 냅켸읕牡켸읕牡켸�
�  � 8 납 4 납 1 납 9 � � � � � � �  � 납 납 납 납 4 납 3 넬컴커 旼왯커旼엿
�  �   납   납   납   � � � � � � �  � 납 납 납 납   납   납 U � � 납 납 납
�  읕컴牡컴켸읕컴牡컴켸 읕� 읕� 읕�  � 납 납 납 납   납   납 7 � � 납 납 납
�   緡敲�敲�敲�敲�敲�敲�敲�敲�敲     읕牡켸읕牡켸읕컴牡컴켸� 7 � 읕牡켸읕冒
� B 낳 볶 볶 볶 볶 볶 볶 볶 볶 �  旼� 旼컴왯커旼왯커旼왯커 읕컴�          �
� A 낳 볶 볶 볶 볶 볶 볶 볶 볶 �  � � �   납 납 납 납 납 넬커旼왯커旼왯커 �
� N 냠�1/4훤1/4훤1/4훤1/4훤1/4훤1/4훤1/4훤1/4훤1/4  � � �   납 납 납 납 납 납 납 납 납 납 � �
� K 냥敲�敲�敲�敲�敲�敲�敲�敲�敲  읕� � U 납 납 납 납 납 납 납 납 납 납 � �
�   낳 볶 볶 볶 볶 볶 볶 볶 볶 �      � 1 냅켸읕牡켸읕牡켸읕牡켸읕牡켸읕� �
� 1 낳 볶 볶 볶 볶 볶 볶 볶 볶 �  旼� � 1 넬커旼왯커旼왯커旼왯커旼왯커    �
�   읜�1/4훤1/4훤1/4훤1/4훤1/4훤1/4훤1/4훤1/4훤1/4  � � � 6 납 납 납 납 납 납 납 납 납 �    �
�   縛커旼왯커旼왯커旼왯커旼왯커  � � �   납 납 납 납 납 납 납 납 납 �    �
� B 납 납 납 납 납 납 납 납 납 �  읕� 읕컴冒 냅켸읕牡켸읕牡켸읕牡켸읕�    �
� A 납 납 납 납 납 납 납 납 납 �         J굼켸旼왯커旼왯커旼왯커旼왯커    �
� N 냅켸읕牡켸읕牡켸읕牡켸읕牡켸  旼�    3�   � 납 납 납 납 납 납 납 �    �
� K 넬커旼왯커旼왯커旼왯커旼왯커  � �         � 납 납 납 납 납 납 납 �    �
�   납 납 납 납 납 납 납 납 납 �  � 쿕켍 J�   읕牡켸읕牡켸읕牡켸읕牡켸    �
� 0 납 납 납 납 납 납 납 납 납 �  � �6�5�4귿컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴�
�   응켸읕牡켸읕牡켸읕牡켸읕牡켸  읕�      �
�                                          �
읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸


1b. LAYOUT

Old Motherboard (also known as the IS/VT286)
     旼컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴횯IP Switch*
     �                   旼컴컴컴컴컴컴컴컴컴컴컴컴횭attery Connector
旼컴�_컴컴컴컴컴컴컴컴컴�_컴컴컴컴컴컴컴컴컴컴커
�  ____ DIPSW          J6� 같� J9  郞袴錮袴袴拷_컴컴Power Supply Connectors
넬커旼왯커旼왯커旼왯커旼풧5같� 같  �PS2賈�PS1�3/4�
납껙남납껙남납껙남납껙남�   _   _컴컴컴컴컴컴컴탠컴�
납콳XPANSION납껙남납껙남�   읕컴컴컴컴컴컴컴컴컵컴컴Keyboard Connector
납껙남납껙남납껙남납껙남� 같캨12_컴컴컴컴컴컴컴탠컴훁ystem Clock Jumper:
납껙남납껙남SLOTS껙남납껙                      �        1-2 Low Mode
납껙남납껙남납껙남납껙남� 같캨7_컴컴커         �        2-3 High Mode
냅켸쳐늘캑쳐느켸쳐느켸쳐� 旼컴컴커   읕컴컴컴컴탠컴횯isplay Type Jumper:
�   남납껙남�   남�   남� 쿎 P U �             �        1-2 Color
�   남납껙남�   남�   남� �      �             �        2-3 Monochrome
�   읕牡켸읕�   읕�   읕� 읕컴컴켸             �
�                            旼컴컴컴컴횶1컴컴컵컴컴Reset Connector
�                            넬컴컴컴컴횶2컴컴컵컴컴RAM Select Jumper:
�   旼컴컴컴컴컴컴커         납                �      1-2 1MB(512/512) Mode
�   �              �         납                �      2-3 512K or 640K Mode
�   � E P R O M    �         납旼컴컴컴횶3컴컴컵컴컴Speaker Connector
�   읕컴컴컴컴컴컴켸         납�               �
넬컴컴컴컴컴컴컴컴컴커       납_� 5 _컴횶4컴컴컵컴컴Power LED & Keylock
납Bank A=(9)64x9     �       �_頰 4 �          �        Connector
납Bank B=(9)64x9     �       _頰� 3 쳐Pin Number
납Bank C=(9)256x1    �       頰頰 2 �          �
납Bank D=(9)256x1    �       頰頰 1 �          �
냅컴컴컴컴컴컴컴컴컴켸        旼컴컴컴컴컴컴컴켸
읕컴컴컴컴컴컴컴컴컴컴컴컴컴컴�

2. SOCKETS

Socket

Chip

Description

U68 MC146818
U81 8742
U99 80287 Math Coprocessor (OPTIONAL)
U110 80286 Main Processor
U122 8259
U125 8259
U129 LOW BIOS (27128 ONLY)
U131 LOW BIOS (27256 ONLY)
U134 HIGH BIOS (27128 ONLY)
U138 HIGH BIOS (27256 ONLY)
U77 6809
U83 8237
U94 8237
U116 74HCT612

3a. JUMPERS

NOTE: This system has no jumpers.

3b. DIP SWITCHES
NOTE: The old version of this motherboard does not have DIP SWITCH 1
Dip Switches (SW1)
旼컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커 EXAMPLE:
� RAM Size         쿞1  S2  S3  S4  S5  S6  S7  S8 �     1 2 3 4 5 6 7 8
쳐컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑 on 幡幡栢栢栢栢幡幡�
� 256k             쿚FF OFF --  --  --  --  --  -- �  _ 栢栢幡幡幡幡栢栢�
� 512k             쿚FF ON  --  --  --  --  --  -- �    賽賽賽賽賽賽賽賽�
� 640k             쿚N  OFF --  --  --  --  --  -- �
� 640k + 384k      쿚N  ON  --  --  --  --  --  -- �
읕컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸
旼컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커
� System Clock     쿞1  S2  S3  S4  S5  S6  S7  S8 �
쳐컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑
� High             �--  --  OFF OFF --  --  --  -- �
� Middle           �--  --  OFF ON  --  --  --  -- �
� Low              �--  --  ON  OFF --  --  --  -- �
� Low              �--  --  ON  ON  --  --  --  -- �
읕컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸
旼컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커
� RESERVED         쿞1  S2  S3  S4  S5  S6  S7  S8 �
쳐컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑
� Reserved         �--  --  --  --  OFF OFF --  -- �
읕컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸
旼컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커
� Display Mode     쿞1  S2  S3  S4  S5  S6  S7  S8 �
쳐컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑
� Color            �--  --  --  --  --  --  ON  -- �
� Monochrome       �--  --  --  --  --  --  OFF -- �
읕컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸
旼컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴커
� 287 Clock Select 쿞1  S2  S3  S4  S5  S6  S7  S8 �
쳐컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴캑
� 10 MHz           �--  --  --  --  --  --  --  ON �
� 4.77 MHz         �--  --  --  --  --  --  --  OFF�
읕컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴컴컴컴컴컴컴컴컴켸

SW2 Settings (ROM Selector)

旼컴컴컴컴컴컴컴컴컫컴컴컴컴컴컴컴커                 EXAMPLE:
� ROM Size         쿞1  S2  S3  S4 �                     1 2 3 4
쳐컴컴컴컴컴컴컴컴컵컴컴컴컴컴컴컴캑                 on 栢栢幡幡�
� 128k             쿚N  ON  OFF OFF�                  _ 幡幡栢栢�
� 256k             쿚FF OFF ON  ON �                    賽賽賽賽�
읕컴컴컴컴컴컴컴컴컨컴컴컴컴컴컴컴켸


4. CONNECTORS

    �袴袴錮袴袴袴袴袴袴袴袴袴袴袴袴袴袴袴�
    � J1  � Keyboard                     �
    � J2  � Battery                      �
    � J3  � Power LED & keylock          �
    � J4  � Speaker                      �
    � J5  � Reset                        �
    � J6  � System clock indicator       �
    훤袴袴鳩袴袴袴袴袴袴袴袴袴袴袴袴袴袴�1/4

5. RISER CARD


NOTE: This system does not have a riser card.