YMF278B

FM Operator Type-L 4 + wave Table Synthesizer (OPL4)

Pinout

            QFP80-(24x16)-14X20MM
+---------------------------------------------+
|  1 A0    |           | 41 WD4   |           |
|  2 A1    |           | 42 WD3   |           |
|  3 A2    |           | 43 WD5   |           |
|  4 *CS   |           | 44 WD2   |           |
|  5 *RD   | 25 *MCS0  | 45 WCO   | 65 VSS    |
|  6 *WR   | 26 *MCS1  | 46 MD6   | 66 *MWR   |
|  7 *IC   | 27 *MCS2  | 47 MD1   | 67 MA6    |
|  8 Vdd   | 28 *MCS3  | 48 MD7   | 68 MA9    |
|  9 *IRO  | 29 *MCS4  | 49 MD0   | 69 MA7    |
| 10 D0    | 30 *MCS5  | 50 *MRD  | 70 MA8    |
| 11 D1    | 31 NC     | 51 MA16  | 71 MA17   |
| 12 D2    | 32 Vdd    | 52 MA0   | 72 Vdd    |
| 13 D3    | 33 NC     | 53 MA15  | 73 MA18   |
| 14 D4    | 34 NC     | 54 MA1   | 74 MA19   |
| 15 D5    | 35 NC     | 55 Vdd   | 75 MA20   |
| 16 D6    | 36 *MCS6  | 56 MA14  | 76 XO     |
| 17 D7    | 37 Vss    | 57 MA2   | 77 XI     |
| 18 Vss   | 38 *MCS7  | 58 MA13  | 78 Vss    |
| 19 CLKO  | 39 *MCS8  | 59 MA3   | 79 *TST1  |
| 20 BCO   | 40 *MCS9  | 60 MA12  | 80 *TST2  |
| 21 LRO   |           | 61 MA4   |           |
| 22 DO0   |           | 62 MA11  |           |
| 23 DO1   |           | 63 MA5   |           |
| 24 DO2   |           | 64 MA19  |           |
+---------------------------------------------+

Frequency

QFP80
Set reader to FREQ, put black probe to GND, red probe to 19, 77 and 78 to measure CPU clock

External links

Yamaha YMF278 page on Wikipedia Yamaha chips page on vorc.org

Files

• 
  YMF278B Datasheet