Thomas,
You are correct both cards have male connectors. You could still use the 68M-50F connector if you use a 68-68 cable. Or if you had a 68F-50M then you would need a 50 pin cable. I have found another option, the R6850-D1 Cable(part number 777419-01) . This is a digital cable that was made to use our 68 pin digital devices with 50 pin breakout boxes. It ties the ground lines together and you also loose access to PFI 37,the up/down pin for counter 0, and you loose the +5V line. I think you may want to check the pin mappings to make sure that you really want to connect these 2 boards directly together. When using a 50 pin conversion with the 6602 you will get the following pin mapping:
Pin Number (1-50) 6602 Signal Name
1 PFI_25
2 PFI_28
3 PFI_27
4 PFI_24
5 PFI_30
6 PFI_31
7 PFI_26
8 PFI_29
9 PFI_21
10 PFI_23
11 PFI_19
12 PFI_17
13 PFI_18
14 PFI_16
15 PFI_22
16 PFI_20
17 GND
18 PFI_34
19 GND
20 PFI_35
21 GND
22 PFI_33
23 GND
24 PFI_32
25 GND
26 GND
27 PFI_38
28 GND
29 Reserved
30 GND
31 PFI_36
32 GND
33 PFI_39
34 GND
35 PFI_4
36 PFI_6
37 PFI_0
38 PFI_2
39 PFI_1
40 PFI_3
41 PFI_7
42 PFI_5
43 PFI_13
44 PFI_10
45 PFI_15
46 PFI_14
47 PFI_8
48 PFI_11
49 PFI_12
50 PFI_9
You will loose half of the cards functionality since half the pins (even numbered pins) will be connected to ground on the 6503. It would be easy for you to short lines to ground this way. It would probably be better if you get a breakout box for each card (SCB-50 and SCB-68) and then connect only the lines you want to share between the cards. So in answer to your question, yes you CAN connect then directly together, but do so with caution, and I do not feel this direct connection is the best solution for y
ou.
Hope this helps.
Kevin R