Fostex A-8 - Page 19

PT 1 -• ■ — 1 1 ------ 1 1 ------ ■ -------- ------ - 1 — 1 -------- ' — ' ------- ------- —
pT2 — i i —      i i  — r i i — i i — i □
u? 4 _rLJi_TLJLJ_Ji — n_TL ______ n_ii ____ n_n_n_n_n_n_Ji
Ut-2 --- 1 1 --- 1 f I ---- 1 1 1 i --- J I --- i L
. n n n n ______ n n ___________ n n n n n
UP/DQWN 1 ________________________________ 1 1 ___ 1
us-a n n _____ n ____ n ______ n n ____________ n n n n n
1 ------- 1 1 1 _______ 1 1 _____________ 1 l_J I _____ 1
w 14 1 _____ 1 — 1 _____ 1 1 _____ 1 1 __ _J l_ ___ 1 l_
\\ ___ r
us-io n ___________ n ____________ ii __________________ n _____ n __________ n_
HIGH SPEED
Fig. 4-7
4.8 COUNTER SECTION
Ui is the P-MOS type tape counter LSI which contain both a counter circuit
and display driver. Display is of the static type.
* UP/DWN ; Input pin for selecting up count or down count of the counter. An
"H" level must be applied to this Ul-12 pin for up count function.
As shown by the timing chart in Item 4.7, above, these outputs go
to "H ” level in the PLAY or F.FWD modes and thus UI goes to up
count mode.
In the ZERO RTN or REWIND modes, an "L" level is applied to Ul-12
and the counter thus goes to the down count mode.
* COUNT PULSE : Thecount pulse is obtained from Q6 on the System Control PCB. The
count pulse is about 4Hz at beginning of tape wind and about 8Hz
near end of tape wind.
* DIRECT ; Input pin for selecting the operating mode of the predivider, in
the stage prior to the lowest digit of the counter, to 1/5 or 1/1.
As the 1/5 mode is used in this system, this pin is open or at "L".
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