Hatte gerade mal wieder Infos zu SASI gesucht und dachte mir, ich stelle das mal hier ein, da es doch manchmal "doof" ist, wenn man was sucht. Die wichtigsten Infos habe ich mal herausgeschrieben, da ich Infos eigentlich immer gern im Textformat habe.
Taken from Shugart SA1400 document:
SASI - Shugart Associates System Interface
The SASI bus structure consists of nine control lines and nine data lines on a 50-pin bus.
All bus lines are implemented as low-true signals.
(Odd lines are ground)
2 DB(0) Data bus 0
4 DB(1) Data bus 1
6 DB(2) Data bus 2
8 DB(3) Data bus 3
10 DB(4) Data bus 4
12 DB(5) Data bus 5
14 DB(6) Data bus 6
16 DB(7) Data bus 7
18 DB(P) Data bus parity-odd
20-30 - Spare
32 ATN Attention
34 - Spare
36 BSY Busy
38 ACK Acknowledge
40 RST Reset
42 MSG Message
44 SEL Select
46 C/D Control/Data
48 REQ Request
50 I/O Input/Output
DB(0-P) These eight bi-directional lines plus optional parity are used
to transfer 8-bit parallel data to and from a host adapter.
BSY is asserted in response to the SEL line from the host;
it indicates that the SASI bus is in use.
ACK is asserted in response to the REQ line from the host; it is an
acknowledgement by the controller that the host wants to perform
a REQ/ACK handshake
RST resets the controller by returning the microprocessor in the
controller to the beginning of its microcode
MSG Asserted by the controller to indicate that a command is complete.
It is always followed by the assertion of I/O and REQ.
SEL is asserted by the host in order to select a controller.
C/D When asserted, the information transmitted across the bus will
be the command or status bytes (i.a. "control" information).
When de-asserted, the information will be data or sense bytes.
REQ is a request for a data transfer; it operates in conjunction
with I/O, C/D and MSG. When asserted and I/O is asserted, REQ
will mean that data on the host bus is driven by the controller;
when asserted and I/O is deasserted, REQ will mean that the data
is driven by the host adapter.
I/O Asserted by the controller to indicate the direction of information
transfer on the data bus lines during a REQ/ACK handshake. I/O is
"input" to the host, when asserted.
Up to 5 Memory devices may be connected per controller
5 1/4" Floppies SA400/410/450/460
5 1/4" Winchester SA600 Series
8" Floppies SA801/851
8" Winchester SA 1000/1100 Series
14" Winchester SA4000 Series
1/4" Tape Cartridge DEI/Archive Tape Cartridge