SM1126 查看數據表（PDF） - Nippon Precision Circuits

零件编号

产品描述 (功能)

生产厂家

SM1126

Melody IC with Built-in SRAM

Nippon Precision Circuits  

SM1126 Series

Command summary

Command

Melody start command

Write command

Tempo word

Melody word

End word

End-of-write command

Parity check command

MSB

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

LSB

1

0

0

0

B3

B2

B1

B0

1

1

0

1

1

1

1

1

0

0

0

T4

T3

T2

T1

T0

R2

R1

R0

S4

S3

S2

S1

S0

0

1

0

1

1

1

1

1

1

0

1

1

1

1

1

1

0

1

1

1

1

1

1

1

Musical Specifications

Maximum program steps

A maximum of 256 steps can be programmed into mask-programmable ROM, and a maximum of 64 steps

(including one end word) can be stored in built-in SRAM. Each step represents either a note (sound pitch and

length) a rest, or a tie.

Note length (including rests)

Eight rhythm values for notes and rests can be programmed. Also, 2 or more notes can be musically tied.

Table 3. Rhythm values

Code

Type

0

1

2

3

4

5

6

7

Note

Rest

Pitch and scale

SM1126 Series devices support 27 pitches from F4 to G6. The pitch varies with the clock frequency, as

shown in the frequency listing in table 4. The reference clock selected at master-slice does not affect the pitch

range.

Also, two pitches higher than G6 can be set as alarm pitches in mask ROM. Note that an alarm pitch option

cannot be specified in SRAM.

The frequency error calculation for a given pitch is shown below.

Error calculation: (A4 pitch with 32.768 kHz clock)

1200 × log2R----Oe---f--ue---tr-p-e--un---tc---ef--r--fe--r-q-e--u-q--e-u--n-e--c-n-y--c--y--

=

1200

×

l--o---g---1---0---R--------Oe------f---u-e-----t-r--p--e----un------tc------ef----r----fe----r--q--e----u--q----e--u---n---e---c--n---y---c-----y----

log 10 2

≈

3986.3

×

log 10

----O-----u---t-p---u---t---f--r--e---q---u---e---n---c--y------

Reference frequency

≈

3986.3

×

log 10

4---3---9---.--8---3---9-

440.000

≈ –0.63 cent

NIPPON PRECISION CIRCUITS—14

Share Link: