Telefunken RT200 User Information page 12

Pin No. Name
1 Vss
2 OSC OUT
3 OSC1
4 OSC2
5 CLOCK1
6 CLOCK2
7 VCC CLOCK
8 PD OUT
9 LATCH CLOCK Input
10 DAIN 3
11 DAIN 2
12 DAIN 1
13 DAIN 0
14 VCC
15 AM LOIN
16 FM LOIN
17 SW/MW
18 FM/AM
Though this helps understanding the circuitry, it doesn't help us with out new firmware, since there is no
information about how to program the synthesizer to a certain frequency. After a couple of phone calls
with Panasonic/Matsushita Germany, it was clear that I would have had to contact the japanese mother
company to get this piece of information (the people I spoke to however were quite friendly and trying to
help me, I must add at this point!).
Since I also own a still working RT200, there was a simpler way of finding things out: take a working
sample, tap onto the data and clock lines, and see what is happening when the frequency changes. I was
able to use a digital logic analyzer from HP for this job:
Direction
---- Ground
Output Goes high if PLL has locked
---- Connect to 4.5 MHz crystal
----
Output 562.5 kHz clock for CPU
Output 250 kHz clock for CPU timer
---- +5V supply
Output Output of Varicap voltage
(externally amplified with 741 OpAmp)
control signal from CPU
Input Data/Address input from CPU
Input
Input
Input
---- +5V supply
Input Input from AM oscillator
Input Input from FM oscillator
Input Select short or medium AM wave band
(unused, tied low)
Input Select AM or FM operation
Function
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