Hi,
Sorry I missed your last post.
I connected the test pin to the Perc audio out ( pin 97 ).
Here is a complete list of all the SK-1 / 5 CPU pin details:
CASIO SK series CPU chip pin details
Pin(s) Name IO What it does
1 BGND Supply Ground or 0V supply for the A/D within the CPU
2 VACD Supply Neg 5v Supply for the A/D within the CPU
3 W-Noise unknown W-noise pin Currently not used on the SK-1
4 M-Noise unknown M-noise pin Currently not used on the SK-1
5-11 IO0 - IO6 Bi Direct 7 data bus lines used to send / receive data from ROM and RAM
12 A0 Out Part of Address bus - A 0
13 IO7 Bi Direct Remaining 8th line for Data bus ( see pins 5-11 )
14 A1 Out Part of Address bus - A 1
15 CE Out Chip enable signal for the CPU to select either ROM or RAM
16-18 A2,A10,A3 Out Part of Address bus - A2, A10, A3
19 OE Out Output Enable signal to allow the RAM to put data onto data bus
20-30 A4-9, A11-15 Out Rest of Address bus A4-A9 and A11 - A15 (sixteen lines in total )
31 WE Out Write Enable signal. When Low the CPU writes data to the RAM
32 RFSH Out Refresh Signal output. When Low the CPU refreshes Ram
33 TIN In Not used on SK-1 Pulled to VDD2, maybe a Test pin
34 TC0 In Not used on SK-1 Pulled to VDD2, Some sort of bit input
35 TC1 In Not used on SK-1 Pulled to VDD2, Some sort of bit input
36 TOUT Out Not used on SK-1 Pulled to VDD2, Something to do with TC0 and TC1
37 ADCTR In Not used on SK-1 Pulled to VDD2, Something to do with internal A/D
38 WE Out Write enable signal, not used on SK-1 but for driving extra devices
39 CE Out Chip enable signal, not used on SK-1 but used on SK-5 to drive Percussion Chip
40 GND Supply 0V supply for the CPU
41 CE2 Out 2nd Chip enable Signal, unused on SK-1 but used on SK-5 to drive Demo Rom Chip
42 TEST In Test pin, worth experimenting with!
43 VDD1 Supply Neg 5v Supply for the CPU
44 VDD2 Supply Used to connect the Unused pins to a voltage source Internal analogue Ground
45 POFF unknown Power Off? Not used on the SK1 or SK5
46 C1 Out Not used on SK-1, left floating but used on SK-5 as clock for Demo Rom
47 C2 Out Not used on SK-1, left floating but used on SK-5 as clock for Demo Rom
48 OP Out Not used on SK-1, left floating but used on SK-5 to select between data / address on Demo Rom
49-56 Aux D0 - D7 Bi Direct Secondary data bus D0 - D7. Unused on SK-1 but drives SK-5 percussion Chip / Demo Rom
57 OSI In Master clock oscillator inputs for 7.24Mhz oscillator
58 OSO Out Master clock oscillator output for 7.24Mhz oscillator
59 MI In Not used on SK-1, left floating but used on SK-5 as input for Power on Detector circuit
60 RESET In Reset in put signal. Pulsed high it will initialize the CPU
61 K015 Out Control signal for external filter circuit, not used on the SK-5
62 K014 Out Not used on SK-1 but determines Accomp volume control signal on SK-5
63 K013 Out Not used on SK-1 but used as RAM / ROM select signal on SK-5
64 K012 Out Not used on SK-1 but used as Auto Power of signal on SK-5 ( pin 86 om SK-1 )
65-76 K011 - K0 Out Key Out signals used to scan the Keyboard and Buttons (K011, K010 unused on SK-1)
77-84 KI1 - KI8 In Key and switch input signals
85 PO0 Out Not used on SK-1 but used as a Reset signal for SK-5 percussion Chip
86 PO1 Out Auto Power Off, when Low switches off the power supply. ( cut this to keep power on )
87 PO2 Out Unused IO pin for both SK-1 and SK-5
88 PO3 Out Control signal for external filter circuit, not used on the SK-5
89 EH Out Analogue Envelope control signal for Melody channel ( CH1 )
90 EG Out Analogue Envelope control signal for Obbligato channel ( CH2 )
91 EF Out Analogue Envelope control signal for Chord channel ( CH3 )
92 EE Out Analogue Envelope control signal for Bass channel ( CH4 )
93 SH Out Analogue Audio Pitch signal for Melody channel ( CH1 )
94 SG Out Analogue Audio Pitch signal for Obbligato channel ( CH2 )
95 SF Out Analogue Audio Pitch signal for Chord channel ( CH3 )
96 SE Out Analogue Audio Pitch signal for Bass channel ( CH4 )
97 SC Out Analogue Audio output for Percussion sounds, not used on SK-5
98 AGND Supply Ground or 0V supply for the D/A within the CPU
99 VDAC Supply neg 5v source for D/A within the CPU
100 VIN input Sample sound data enters the CPU here
Hope this is useful!
Cheers
Paul