Z90251 ZILOG [Zilog, Inc.], Z90251 Datasheet - Page 76

• Manufacturer Part Number: Z90251
• Description: eZVision 200 Television Controllers with OSD
• Manufacturer: ZILOG [Zilog, Inc.]

9
Pulse Width Modulators
9.1
Table 53 IR Capture Register 1 04h: Bank C (IR_CP1)
The Z90255 has 11 Pulse Width Modulator channels. PWM1 through PWM10 have
6-bit resolution and are typically used for audio and video level control. PWM11 has
14-bit resolution and is typically used for voltage synthesis tuning. PWM11 uses
two registers to accommodate its 14-bit resolution. PWM6 can be configured as
either 14-bit or 6-bit.
PWM Mode Register
PWM Mode Register (Table 54) controls the setting of multiplexed pins 1-7. These
pins can be configured to function as PWM output ports or regular output ports. If
a bit is reset to 0, the pin outputs the PWM signal. If a bit is set to 1, the pin is a
regular output port.
Table 54 PWM Mode Register 0Dh: Bank B (P_MODE)
Bit
R/W
Reset
Note: R = Read W = Write X = Indeterminate
Bit/
Field
IR Capture Register 1
Bit
R/W
Reset
Note: R = Read W = Write X = Indeterminate
R
7
0
R/W
7
0
Bit
Position
7,6,5,4,3,2,1,0
R
R/W
6
0
6
1
R/W
R
5
0
5
1
R/W
32 KB Television Controller with OSD
R
R/W
R
4
0
4
1
Value Description
R/W
R
3
0
3
1
Reading High Byte of IR
Capture Data
R/W
R
2
0
2
1
R/W
PS001301-0800
R
1
0
1
1
R/W
R
0
0
0
1
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