sh6612a SinoWealth Micro-Electronics Corp. Ltd, sh6612a Datasheet - Page 14

• Manufacturer Part Number: sh6612a
• Description: 2k 4-bit Microcontroller With Lcd Driver
• Manufacturer: SinoWealth Micro-Electronics Corp. Ltd

10. ALARM envelope control
System Register $14:
Default carrier frequency is 4KHz. Can be selected to 2KHz by code option.
WRITE mode: control the envelop selection.
READ mode can read out current envelope wave forms.
Below is the ALARM functional block equivalent circuit diagram. To activate the ALARM function, first switch the PAM to
ALARM OUTPUT mode. After setting PAM equal to 1, then set the proper envelope. When the data writes into AEC, the
envelope counter will be synchronized at the same time. The programmer can read back the envelope from AEC register
and make any pattern changes needed by programmer. The Read operation will not affect the alarm output waveform.
The programming alarm waveform is shown below (32.768KHz crystal or 262K RC):
$14
AEC3
Bit 3
OSCO
X
X
X
0
1
OSCI
/4
AEC2
Bit 2
0
X
X
1
X
1
BD OUTPUT 2K or
AEC1
Bit 1
3
X
X
X
0
1
4k
AEC = $C
AEC = $A
AEC = $0
AEC = $8
AEC = $F
4
PAM = 1
PAM = 1
PAM = 1
PAM = 1
PAM = 1
16H
mask option
4K or 2K
8H
4H
2H
1H
z
z
z
z
z
6
AEC0
Bit 0
0
1
X
X
X
8
R/W
R/W
9
14/24
10
11
ALARM envelope control
DC envelope
1Hz envelope
2Hz envelope
4Hz envelope
8Hz envelope
32K or 262K
mask option
16Hz
R
Remarks
8Hz
R
4Hz
R
2Hz
R
1Hz
R
RD $14
WR $14
To Sound
Mixer
SH6612A
Power On
Yes
Ver 0.3