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Chapter 18
Sound Generator
User’s Manual U16504EE1V1UD00
(1)
Sound generator control register (SGCR)
SGCR is a register which sets up the following four types.
Controls sound generator output
Selects output of sound generator
Selects sound generator input frequency f
SG1
Selects 5-bit counter input frequency f
SG2
SGCR is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input clears SGCR to 00H.
Figure 18-3 shows the SGCR format.
Figure 18-3:
Sound Generator Control Register (SGCR) Format (1/2)
Caution:
Before setting the TCE bit, set all the other bits.
Remark:
SGOF :
SGO
SGOA :
Basic cycle signal (without amplitude)
Basic cycle signal (with amplitude)
Amplitude signal
:
Symbol
SGCR
7
6
0
5
0
4
0
3
2
1
0
Address
FFC0H
After Reset R/W
00H
TCE
SGOB
SGCL2 SGCL1 SGCL0
R/W
TCE
Sound Generator Output Selection
0
Timer operation stopped
SGOF/SGO and SGOA for low-level output
1
Sound generator operation
SGOF/SGO and SGOA for output
SGOB
Sound Generator Output Selection
0
Selects SGOF and SGOA outputs
1
Selects SGO and PCL outputs
SGCL2
SGCL1
5-Bit Counter Input Frequency f
SG2
Selection
0
0
f
SG2
= f
SG1
/2
5
0
1
f
SG2
= f
SG1
/2
6
1
0
f
SG2
= f
SG1
/2
7
1
1
f
SG2
= f
SG1
/2
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