At 4:23 PM +0300 9/8/00, Detelin Batchovski wrote:
>ok, I will try varios combinations to enter OpenFirmware.
>But is that pin-out wright ?
>
>DIN8                        DB9
>pin1                        pin6
>pin2 (or 2 and 7)           pin4
>pin3                        pin2
>pin4 (or 4 and 8)           pin5
>pin5                        pin3

I don't know PC DB9 pin-out at all.  The recommended connection to a 
DB25 connector is:
    DIN8			   DB25			Direction
1	DTR		4,20	DTR&RTS		->
2	CTS		5	CTS		<-
3	TxD-		2	TD		->
4	Ground		7	SG		<->
5	RxD-		3	RD		<-
6	TxD+		NC			->
7	GPi		8	DCD		<-
8	RxD+		7	SG		<-

This is from the Apple Remote Access Modem Scripting Guide: Version 
2.1.  I include the direction because you can use a voltmeter to look 
at the pins as a sanity check to see if the pin-out matches your 
understanding.  Output lines should show around 5 to 12 V either + or 
-.  I don't think the Mac does this, but I did see one RS-232 
implementation where unconnected inputs showed as -2.5 V.  The inputs 
were biased to provide noise immunity if they were unconnected.


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