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ldkraemer
August 5th, 2017, 06:17 AM
The EAGLE I, II, III, IV have a Diagnostic Test built in ROM called the "T" Test. It requires Serial & Parallel Loop Back Cables.
I've figures out the Serial Loop Back Cable as noted below. But, don't know how the Parallel Cable should be constructed.

Does anyone have more information, or have used these Diagnostics, and know what the parallel is testing?


SYSTEM "T" TESTS:

SIO - Page 44
Uses the DART Chip to send data out one serial port, and receive it on the other via the loop
back cable. It then checks the data for errors. The procedure is repeated in the opposite
direction.

Page 103
DB25.............................................D B25
Serial A: Eagle I, II, III, IV...................Serial B: Eagle I, II, IV
1 - FG...........................................1 - FG
2 - RX-------------------------------------------3 - TX
3 - TX-------------------------------------------2 - RX
4 - RTS------------------------------------------5 - CTS
5 - CTS------------------------------------------4 - RTS
7 - Signal Ground--------------------------------7 - Signal Ground
All other Pins - No Connection



PIO - Page 44
Uses the two Parallel Input Output IC's to send data out one parallel port and receive it on
the other. It then checks the data for errors.

Page 104
Parallel A: Eagle I, II, III
1 -- NC
2 -- NC
3 -- NC
4 -- NC
5 -- NC
6 -- GND
7 -- NC
8 -- GND
9 -- BUS DIR
10 - GND
11 - NC
12 - DRIVE ACK
13 - NC
14 - NC
15 - NC
16 - COMPLETE
17 - GND
18 - NC
19 - HDD6
20 - HDD7
21 - HDD4
22 - HDD5
23 - HDD2
24 - HDD3
25 - HDD0
26 - HDD1
27 - READY
28 - GND
29 - STROBE
30 - GND
31 - HDREST
32 - GND
33 - NC
34 - NC

Parallel B: Eagle I, II, & Parallel Printer IV
1 -- DATA STROBE
2 -- DATA 1
3 -- DATA 2
4 -- DATA 3
5 -- DATA 4
6 -- DATA 5
7 -- DATA 6
8 -- DATA 7
9 -- DATA 8
10 - NC
11 - BUSY
12 - NC
13 - ON LINE
14 - NC
15 - NC
16 - SIGNAL GROUND
17 - GND
18 - NC
19 - GND
20 - GND
21 - GND
22 - GND
23 - GND
24 - GND
25 - GND
26 - GND
27 - GND
28 - NC
29 - GND
30 - GND
31 - NC
32 - NC
33 - GND
34 - NC
35 - NC
36 - NC


Typical Parallel Loop Back Plug:
STROBE - SELECT IN
DATA0 - ERROR IN
AUTO FD - PAPER END INPUT
INIT - ACKNOWLEDGE INPUT/CD
SELECT OUT - BUSY INPUT


Thanks.

Larry