The DAC output is a digital current output. To convert to voltage, use a resistor ladder (R-2R) or simply a 1k resistor to ground followed by a buffer amplifier. The datasheet recommends:
Do you need an to interface with it?
| 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 | kc89c72 datasheet
When storing KC89C72 chips, keep them within the temperature range of to avoid physical damage. Like all CMOS ICs, the KC89C72 is sensitive to electrostatic discharge (ESD) . Use proper anti-static measures such as grounded workstations, anti-static bags, and wrist straps when handling the chip. Store the device in ESD-safe packaging and avoid exposure to moisture, dust, or corrosive environments.
| 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 | The DAC output is a digital current output
Example minimal C setup (SDCC-like pseudocode):
| Feature | KC89C72 | AY-3-8912 | Yamaha YM2149 | | :--- | :--- | :--- | :--- | | Technology | CMOS | NMOS | NMOS (but more common) | | Pin Count | 28 | 28 | 40 (or 28 in some variants) | | I/O Ports | None (pins N/A) | None (removed) | Two 8-bit ports | | Noise | Shared (w/ tone) | Same | Same (but different pol.) | | Supply Current | ~5 mA @ 2 MHz | ~30 mA | ~30 mA | | Availability | Scarce (vintage) | Rare | Widely available (eBay, etc.) | | Software Compatibility | 100% (AY-3-8910) | 100% | 99% (different mixer bit) | | Pin | Name | Type | Description
The next time you come across a dusty PDF titled "KC89C72 Datasheet," do not scroll past it. Open it. Look at the block diagram, the timing waveforms, the tiny Cyrillic annotations. You are holding a document that is at once a technical manual, a spy novel, and a eulogy. It is proof that even in the most rigid, formulaic genre of technical writing—the datasheet—there exists the potential for drama, ingenuity, and survival. In the end, a chip is just silicon. But its datasheet? That is its soul.
LD A, 0x08 ; Select R8 (Amplitude A) OUT (0x80), A LD A, 0x0F ; Max volume (16-level) OUT (0x81), A