Command Codes To The System; Ack(Hex Fa) - IBM 5170 Technical Reference

The following figure lists the positions of the keys and their make
scan codes.
Kev Positions and Their Make Codes
1--0E 18--10 36--33 55--4A
90--76
2--16 19--24 37--38 56--51
91--6C
3--1E 20--20 38--42 57--59
92--68
4--26 21--2C 39--48 58--11
93--69
5--25 22--35 4O--4C 60--19 94--77
6--2E 23--3C 41--52 61--29
96--75
7--36 24--43 43--5A 64--58
97--73
8--30 25--44
44--12
65--06
98--72
9--3E 26--40 46--1A 66--0C
99--70
10--46 27--54 47--22 67--08 100--7E
11--45
28--58
48--21 68--0A
101--70
12--4E 30--14 49--2A 69--09 102--74
13--55 31--1C 50--32 70--05
103-7A
14--50 32--18 51--31 71--04
104--71
15--66 33--23 52--3A 72--03
105--84
16--00 34--28 53--41
73--83 106--7C
17--15 35--34 54--49 74--01
107--78
Make Scan Codes
Command Codes to the System
The command codes described here are those sent by the
keyboard. The codes have a different meaning when issued by
the system.
Resend (Hex FE)
The keyboard issues a Resend command following receipt of an
invalid input, or any input with incorrect parity.
If
the system
sends nothing to the keyboard, no response is required.
ACK(Hex FA)
The keyboard issues an
I
ACK
I
response to any valid input other
than an Echo or Resend command. If the keyboard
is
interrupted
4-12 Keyboard