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			<title>Lisa/Macintosh XL: RS-232 and RS-422 Pinouts for Serial Port B</title><body class="ac-gn-current-support">
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<h1 id="main-title">Lisa/Macintosh XL: RS-232 and RS-422 Pinouts for Serial Port B</h1>
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The signals available on Serial Port B of the Lisa are shown in<BR>
Figure 3-9, page 3-24 of the Lisa Hardware Manual (for RS-232) and<BR>
on page 3 of Macintosh Technical Notes #10 (for RS-422). This data is<BR>
combined here.<BR>
 <BR>
Pin No.   RS-232 Name               RS-422 Name      Notes<BR>
 <BR>
1         Ground                    Ground<BR>
2         Transmit data             TxD-<BR>
3         Receive data              RxD-<BR>
4         Request to send<BR>
6         Data set ready            HSK/DSR          TRxCB or CTSB<BR>
7         Ground                    Ground<BR>
19        AppleTalk receive data    RxD+<BR>
20        Data terminal ready       TxD+/DTR         Connected to DTRB<BR>
 <BR>
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<div class="mod-date">Published Date: Feb 18, 2012</div>
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