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Kc89c72 Datasheet [Certified]

The datasheet provides frequency calculation formulas: [ \textTone Period = \frac\textClock Frequency16 \times \textDesired Frequency - 1 ] Q: Is the KC89C72 still in production? A: No. It has been obsolete since the late 1990s. Only NOS (new old stock) or used pulls are available on eBay or surplus electronics sites.

; Assume KC89C72 base address = 0x80 ; Write to address register LD A, 0x00 ; Select R0 (Tone A low byte) OUT (0x80), A ; Write data to selected register LD A, 0x7E ; Low byte value for 440Hz at 1MHz OUT (0x81), A LD A, 0x01 ; Select R1 (Tone A high byte) OUT (0x80), A LD A, 0x02 ; High byte value OUT (0x81), A kc89c72 datasheet

| Register | Function | |----------|-----------------------------------------------| | R0 | Tone A period (fine, bits 0–7) | | R1 | Tone A period (coarse, bits 8–11) | | R2 | Tone B period (fine) | | R3 | Tone B period (coarse) | | R4 | Tone C period (fine) | | R5 | Tone C period (coarse) | | R6 | Noise period (5-bit, bits 0–4) | | R7 | Mixer control (enable/disable tone/noise) | | R8 | Amplitude A (16 levels or envelope) | | R9 | Amplitude B | | R10 | Amplitude C | | R11 | Envelope period (fine) | | R12 | Envelope period (coarse) | | R13 | Envelope shape (attack/decay/cycle) | | R14 | I/O Port A data | | R15 | I/O Port B data | Only NOS (new old stock) or used pulls

| Pin | Name | Type | Description | |-----|----------|--------|--------------------------------------------------| | 1 | DA7 | I/O | Data bus bit 7 | | 2 | DA6 | I/O | Data bus bit 6 | | 3 | DA5 | I/O | Data bus bit 5 | | 4 | DA4 | I/O | Data bus bit 4 | | 5 | DA3 | I/O | Data bus bit 3 | | 6 | DA2 | I/O | Data bus bit 2 | | 7 | DA1 | I/O | Data bus bit 1 | | 8 | DA0 | I/O | Data bus bit 0 | | 9 | /BDIR | Input | Bus direction control (mode select) | | 10 | /BC2 | Input | Bus control 2 | | 11 | /BC1 | Input | Bus control 1 | | 12 | /RESET | Input | Active low reset | | 13 | A8 | Output | I/O port A bit 8 | | 14 | A7 | Output | I/O port A bit 7 | | 15 | A6 | Output | I/O port A bit 6 | | 16 | A5 | Output | I/O port A bit 5 | | 17 | A4 | Output | I/O port A bit 4 | | 18 | A3 | Output | I/O port A bit 3 | | 19 | A2 | Output | I/O port A bit 2 | | 20 | A1 | Output | I/O port A bit 1 | | 21 | GND | Power | Ground (0V) | | 22 | A0 | Output | I/O port A bit 0 | | 23 | B0 | I/O | I/O port B bit 0 | | 24 | B1 | I/O | I/O port B bit 1 | | 25 | B2 | I/O | I/O port B bit 2 | | 26 | B3 | I/O | I/O port B bit 3 | | 27 | B4 | I/O | I/O port B bit 4 | | 28 | B5 | I/O | I/O port B bit 5 | | 29 | B6 | I/O | I/O port B bit 6 | | 30 | B7 | I/O | I/O port B bit 7 | | 31 | NC | - | Not connected (No Connection) | | 32 | NC | - | Not connected | | 33 | ANOD | Output | Analog output – channel A (audio out) | | 34 | ANOD | Output | Analog output – channel A (same as pin 33) | | 35 | BNOD | Output | Analog output – channel B | | 36 | CNOD | Output | Analog output – channel C | | 37 | TEST1 | Input | Factory test – tie to GND | | 38 | TEST2 | Input | Factory test – tie to GND | | 39 | CLOCK | Input | Master clock input (typical 1–2 MHz) | | 40 | VCC | Power | +5V DC | Some later versions of the KC89C72 datasheet show different labeling for analog outputs (e.g., AOUT, BOUT, COUT). Always refer to the exact datasheet revision for your chip date code. Part 3: Electrical Specifications & Timing From the kc89c72 datasheet , here are the key electrical characteristics at T_A = 25°C, VCC = 5V ±5%: Part 3: Electrical Specifications & Timing From the

| Feature | AY-3-8910 (NMOS) | KC89C72 (CMOS) | YM2149 (Yamaha) | |-------------------------|------------------|------------------|----------------------| | Technology | NMOS | CMOS | NMOS | | Power consumption | ~100 mA | ~15 mA | ~50 mA | | Output type | Open-drain | Push-pull | Push-pull (different voltage swing) | | Pinout | 40-pin DIP | 40-pin DIP | 40-pin DIP, pin-compatible | | Noise generator | Yes | Yes | Yes (different PRNG) | | Envelope shapes | 16 | 16 | 16 | | I/O ports | 8+8 bits | 8+8 bits | 8+8 bits |

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