Table 7-1 Truth Table(1)
| INPUTS |
ACTION |
| CLK |
CLR |
| ↑ |
L |
No Change |
| ↓ |
L |
Count |
| X |
H |
All Qs Low |
(1) H = High voltage level.
L = Low voltage level.
X = Dont care.
↑ = Transition from low to high
level.
↓ = Transition from high to low.
Table 7-2 BCD Count Sequence For ½ the
390(1)
| COUNT |
OUTPUTS |
| QD |
QC |
QB |
QA |
| 0 |
L |
L |
L |
L |
| 1 |
L |
L |
L |
H |
| 2 |
L |
L |
H |
L |
| 3 |
L |
L |
H |
H |
| 4 |
L |
H |
L |
L |
| 5 |
L |
H |
L |
H |
| 6 |
L |
H |
H |
L |
| 7 |
L |
H |
H |
H |
| 8 |
H |
L |
L |
L |
| 9 |
H |
L |
L |
H |
(1) Ouput nQA connected to
nCLKB with counter input on
nCLKA.
Table 7-3 B-Quinary Count Sequence For ½
the 390(1)
| COUNT |
OUTPUTS |
| QD |
QC |
QB |
QA |
| 0 |
L |
L |
L |
L |
| 1 |
L |
L |
H |
L |
| 2 |
L |
H |
L |
L |
| 3 |
L |
H |
H |
L |
| 4 |
H |
L |
L |
L |
| 5 |
L |
L |
L |
H |
| 6 |
L |
L |
H |
H |
| 7 |
L |
H |
L |
H |
| 8 |
L |
H |
H |
H |
| 9 |
H |
L |
L |
H |
(1) Output nQD connected
to nCLKA with counter input on
nCLKB.