Casio CTK-750 manual Digital Signal Processor HG51A115A01FD

Digital Signal Processor (HG51A115A01FD)

Upon receipt of note numbers and their velocities, the DSP reads sound and velocity data from the sound source ROM in accordance with the selected tone; the DSP can read rhythm data simultaneously when a rythm pattern is selected. Then it provides 16-bit serial signals containing data of the melody, chord, bass, and percussion to the DAC. The DSP also adds the selected effect to the sound data using a 256k-bit RAM.

The following table shows the pin functions of the DSP.

Pin No.	Terminal	In/Out	Function
1 ~ 8	CD0 ~ CD7	In/Out	Data bus
9, 10			Not used.
11	GND7	In	Ground (0V) source
12	CK16	Out	16.384MHz clock output
13	VCC6	In	+5V source
14	CK0	In	Clock input. Connected to terminal CK16.
15	TCKB		Not used.
16	VCC1	In	+5V source
17	GND1	In	Ground (0V) source
18, 19	XT0, XT1	In/Out	16.384MHz clock input/output. Connected to a crystal oscillator.
20	SGL	In	System control terminal. Single chip system: Open
21	CCSB	In	Chip select signal input
22 ~ 25	CA0 ~ CA3	In	Addess bus
26	CE0	In	Not used. Connected to ground.
27	CWRB	In	Write enable signal
28	CRDB	In	Read enable signal
29 ~ 32			Not used.
33	RESB	In	Reset signal input
34	TESB	In	Not used. Connected to +5V.
35 ~ 39			Not used.
40 ~ 49	RD0 ~ RD15	In	Data bus for the sound source ROM
52 ~ 57
58	RA23	Out	Not used.
59	RA22	Out	Chip select signal for the sound source ROM
60, 61	RA20, RA21	Out	Not used.
62 ~ 73	RA0 ~ RA19	Out	Data bus for the sound source ROM
75 ~ 82
74	GND5	In	Ground (0V) source
83	WOK2	Out	Word clock output. Not used.
84	VCC3	In	+5V source
85	GND3	In	Ground (0V) source
86	WOK1	Out	Word clock for the DAC
87	SOLM	Out	Serial data output. Not used.
88	SOLP	Out	Serial data output for the DAC
89	BOK	Out	Bit clock output for the DAC
90 ~ 92			Not used.

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