TRS-80 Model II #1 type harddisk interface similar to WD1002.

#1 pin   function  WD1002 standard pin (40p)
02       HDDD0*    01
04       HDBD1*    03
06       HDBD2*    05
08       HDBD3*    07
10       HDBD4*    09
12       HDBD5*    11
14       HDBD6*    13
16       HDBD7*    15
18
20       HDBA0*    17
22       HDBA1*    19
24       HDBA2     21
26       HDBA3
28       HDBRD*    27
30       HDBWR*    25
32       HDBMR*    39
34       HDBCS*    23
36
38       HDBDRQ*   37
40       HDINTRQ*  35
42       HDWAIT*
44       HDPINT*
46       HDBNCS
48
50