YM2610

Package	SDIP64
Manufacturer
First use	1990 ?
Used on	All systems

The YM2610 is a sound synthesis and playback chip made by Yamaha, found in all versions of the NeoGeo hardware running at 8MHz. It was later integrated in NEO-YSA and NEO-YSA2, which are used on some versions of the NeoGeo CD, the CDZ, the MV1C and on ROM-Only boards.

The YM2610 requires a YM3016 external DAC (Digital to Analog Converter) chip for the FM and ADPCM channels. The only direct analog output is for the SSG mono sounds. Analog signals are then mixed together externally.

The original YM2610 chip gets quite warm during normal operation due to its use of NMOS technology and dynamic logic, this is normal.

Parts

Sound can be produced from a total of 14 channels, coming from 3 different generators:

• SSG (Software Sound Generator): 3 channels
• FM (Frequency Modulation): 4 channels
• ADPCM A and B (Sample playback): 6 + 1 = 7 channels

Programming

The Z80 CPU is dedicated to driving the YM2610 for music and sound effects.

See Z80/YM2610 interface and YM2610 registers.

Pinout

• SDD: Z80 data bus
• RAD: ADPCM-A multiplexed address/data
• RMPX: ADPCM-A address/data select
• ROE: APDCM-A data output enable
• RA: ADPCM-A address
• ANA: SSG analog output
• SH1: YM3016 latch 1
• SH2: YM3016 latch 2
• OP0: YM3016 serial data
• PA: ADPCM-B address
• POE: ADPCM-B data output enable
• PMPX: ADPCM-B address/data select
• PAD: ADPCM-B multiplexed address/data
• IRQ: Interrupt request output
• CS: Chip select
• WR: Write
• RD: Read
• SDA: Z80 address bus
• PHI M: Clock input
• PHI S: YM3016 clock output

ADPCM bus

See YM2610 ADPCM bus.

Trivia

• The YM2610B is a non-crippled version of the YM2610, with all 6 FM channels enabled.
• The NeoGeo CD has no ADPCM-B capabilities.

Datasheet

• Japanese datasheet: [ajworld.net]
• Incomplete/translated datasheet: [YM2610.pdf]