YM2203

The YM2203 is a FM operator type-N(OPN).OPN (FM OPERATOR TYPE-N) is a new type synthesizer which can produce all sounds required owing to the FM sound source system. It is provided with a built-in register which can store sound information and be connected easily with a microprocessor or microcomputer. It also comprises a square wave sound source different from the sound source according to the FM system and a noise generator.

Features of the YM2203 are:(1)the FM system sound source produce three different sounds simultaneously; (2)one of the above three sounds can be set to the mode by which specific sound effects and composite sine wave sound are synthesized; (3)two programmable timers are incorporated; (4)8 bits general purpose input/output ports of two system are incorporated; (5)three square wave sounds and white noise can be produced in addition to the FM system sounds; (6)clock divider is built in so that wide operating frequency range is obtained; (7)input and output are compatible with TTL; (8)Nch-si-gate MOS LSI is used; (9)single phase power source of 5 v is used; (10)this is compatible with software of YM2149 and AY-3-8910 and 8912 produced by GI.

The absolute maximum ratings of the YM2203 can be summarized as:(1)terminal voltage:-0.3 to 7.0 V;(2)storage temperature:-50 to +125;(3)operating ambient temperature:0 to +70.The OPN is controlled based on the data written into the register. Accordingly, a microprocessor is free from the sound control operation except sending the data to the register.The FM sound source determines a sound by the combination (modulation) of four sin waves.All the modulation systems such as feedback FM, simple FM and multiple FM are possible.In respect to the square wave sound source, this is compatible with YM2149 (SSG) and AY-3-8910 and 8912 (PSG.GI) in the use of the software. Therefore, function of the OPN can be improved by the exchange with the above LSI.