Texas Instruments Tiris 2000 Series, Reference Manual

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ASCII Protocol - Reference Guide May ’00
1 = Logical high, 0= Logical low
The second character after J represents the status of the I/O lines 4 to 7. Table 3
shows the relationship between the character and the status of the lines:
Table 2: Input Line Status
Returned
Character
Status of
I/O 3
Status of
I/O 2
Status of
I/O 1
Status of
I/O 0
0 0 0 0 0
1 0 0 0 1
2 0 0 1 0
3 0 0 1 1
4 0 1 0 0
5 0 1 0 1
6 0 1 1 0
7 0 1 1 1
8 1 0 0 0
9 1 0 0 1
A 1 0 1 0
B 1 0 1 1
C 1 1 0 0
D 1 1 0 1
E 1 1 1 0
F 1 1 1 1
Table 3: Input Line Status
Returned
Character
Status of
I/O 3
Status of
I/O 2
Status of
I/O 1
Status of
I/O 0
0 0 0 0 0
1 0 0 0 1
2 0 0 1 0
3 0 0 1 1
4 0 1 0 0
5 0 1 0 1
6 0 1 1 1
7 0 1 1 1
8 1 0 0 0
9 1 0 1 0
A 1 0 1 0
B 1 0 1 1
C 1 1 0 0
D 1 1 0 1
E 1 1 1 0
F 1 1 1 1