Lsi (Hd43110) - Radio Shack TRS-80 Service Manual

3. LSI (HD43110)
HD43110 is a cassette tape interface LSI with Kansas City standards which transfers data between
the CPU and cassette tape recorder.
Data "0" and "1" are transferred in serial as 1,170 Hz and 2,340 Hz frequency pulse respectively.
Data is transferred at 300 bits per second.
The following lists the functions of each terminal of the LSI.
Pin No. Signal Name In/Out Function
2
OSC
In Clock pulse (32,768Hz) input.
- - - - - - - _ . -
7
VDD' Out -3Voutput.
8
CONT In The LSI functions only when'
the terminal is HIGH .
.
_ - . -
9 VDD1 In
-3V input.
10 CE In
Chip enable terminal. The LSI
is designated from PC- 4 when
the terminal is HIGH.
11 SP In Strobe pulse input from PC-4.
13
04 In/Out Serial data input/output.
14 GND In OV input terminal.
17
C3 In Data input from cassette tape.
18 C2 Out Data output to cassette tape.
19 C1
Out
Remote control (auto stop)
signal output.
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