16 16-BIT AUDIO PWM TIMER (T16P)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
16-3
3.1.1 Internal Clock (PCLK1 Division Ratio) Selections
Table 16.
CLKDIV[3:0]
Division ratio
CLKDIV[3:0]
Division ratio
0xf
Reserved
0x7
1/128
0xe
Reserved
0x6
1/64
0xd
Reserved
0x5
1/32
0xc
1/4096
0x4
1/16
0xb
1/2048
0x3
1/8
0xa
1/1024
0x2
1/4
0x9
1/512
0x1
1/2
0x8
1/256
0x0
1/1
(Default: 0x0)
Note: Make sure the counter is halted before setting the count clock.
For controlling PSC Ch.0, refer to the “Prescaler (PSC)” chapter.
PCM Data Configuration
16.3.2
The resolution and data format must be specified for manipulating PCM data.
Data resolution
T16P supports 8-bit and 16-bit PCM data. Use RESSEL/T16P_CTL register to select the resolution. When
RESSEL is set to 1 (default), 16-bit resolution is selected; when set to 0, 8-bit resolution is selected.
Notes: • 16-bit audio data must be written to address 0x301200 (CMPA[15:0]/T16P_A register) in 16-
bit size.
• 8-bit audio data must be written to address 0x301201 (CMPA[15:8]/T16P_A register) in 8-bit
size. Furthermore, select 8 bits + 8 bits split mode to use 8-bit audio data (RESSEL = 0). The
PWM pulse will be output from the PWM_H pin and the PWM_L pin is fixed at the level set by
INITOL. In this case, the PWM_L pin can be used for a GPIO or other function.
Data format
T16P supports signed and unsigned PCM data. Use SGNSEL/T16P_CTL register to select the data format.
When SGNSEL is set to 1 (default), signed data format is selected; when set to 0, unsigned data format is se-
lected.
Note: When signed audio data is selected, CMPA15/T16P_A register is treated as the sign bit for both
16-bit and 8-bit audio data.
Operating Mode Selection
16.3.3
Split mode
When 16-bit PCM data is used, it can be manipulated by splitting into two data units. Use SPLTMD[1:0]/
T16P_CTL register to select a split mode.
3.3.1 Split Mode Selection
Table 16.
SPLTMD[1:0]
Split mode
0x3
10 bits + 6 bits split mode
0x2
9 bits + 7 bits split mode
0x1
8 bits + 8 bits split mode
0x0
16 bits normal mode
(Default: 0x0)
When a split mode is selected, the split high-order bits (10, 9, or 8 high-order bits) of the compare A data and
the low-order bits (6, 7, or 8 low-order bits) are compared with the counter data and the two comparison results
generate two PWM output signals. The PWM signal generated from the high-order data bits is output from the
PWM_H pin and another generated from the low-order data bits is output from the PWM_L pin. When a split
mode or 8-bit PCM data resolution is selected, compare A interrupts cannot be generated.