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Zen Harris edited this page Jul 24, 2015 · 1 revision

and here are the details of how to wire the IDE disk to the AA connector on a SYM-1. This was done by my associate on the Symbiosys project cjb, seen also on this forum with his parallel port data transfer system for connection the SYM to the lpt port on a linux machine, he also wrote the IDE device sector R/W driver in Symbiosys. So this is where the whole thing started a little less than a year ago now.

No additional hardware is necessary for the IDE interface.  
Connecting a 6522 VIA to an ATA IDE bus
---------------------------------------
Designed for a Synertek SYM-1, and its AA Expansion connector.

PORTB0-7 maps to DATA0-7 on IDE

PORTA0 = ADDR0
PORTA1 = ADDR1
PORTA2 = ADDR2
PORTA3 = /RD
PORTA4 = /WR
PORTA5 = /CS0


AA-pin         AAname*                   IDE

1               GND            2,19,22,24,26,30,40,Power-
3               A1                15 (DATA1)
7               B5                37 (/CS0)
8               B3                25 (/RD)
9               B1                33 (ADDR1)
10              A7                3  (DATA7)
11              A5                7  (DATA5)
12              A3                11 (DATA3)
13              RESET             1  (jumpered)

A              Vcc                 Power+
C              A2                 13 (DATA2)
D              A0                 17 (DATA0)
J              B4                 23 (/WR)
K              B2                 36 (ADDR2)
L              B0                 35 (ADDR0)
M              A6                 5  (DATA6)
N              A4                 9  (DATA4)

                                  27 (IORDY) - tie low 10kR
                                  29 (DMACK) - tie high 1kR
                                  38 (/CS1)  - tie high 1kR
                                  39 (DASP)  - LED+180R to Vcc


*: as I discovered when debugging the code, what
the SYM1 calls PORT A on its AA expansion bus, is
actually PORTB to the 6522. The pinout is no different,
since I ended up changing the code to suit.

-- 
Chris Baird,, <cjb@brushtail.apana.org.au> Feb2010.
Corrected IORDY and DASP: 2010-Jul-31
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