saa5288 NXP Semiconductors, saa5288 Datasheet - Page 9

• Manufacturer Part Number: saa5288
• Description: Microcontroller With Full Screen Screen Display
• Manufacturer: NXP Semiconductors

Philips Semiconductors
7.3.5
Eight 6-bit DACs are available to allow direct control of analogue sections of the television.
Each low resolution 6-bit DAC is controlled by its associated Special Function Register (PWM0 to PWM7). The PWM
outputs are alternative functions of Port 2 and P3.4. The PWE bit in the SFR for the port corresponding to the PWM
should be set to logic 1 for correct operation of the PWM, e.g. if PWM0 is to be used, P2.1 should be set to logic 1 setting
the port pin to high-impedance.
7.3.5.1
Table 3 Pulse Width Modulator Registers (see Table 10 for addresses)
Table 4 Description of PWMn bits (n = 0 to 7)
1997 Jun 24
TV microcontroller with full screen
On Screen Display (OSD)
PWE
BIT
7
7
6
5
4
3
2
1
0
6-
Pulse Width Modulator Registers (PWM0 to PWM7)
BIT
PWM DAC
SYMBOL
PWE
PV5
PV4
PV3
PV2
PV1
PV0
6
S
If PWE is set to a logic 1, the corresponding PWM is active and controls its assigned
port pin. If PWE is set to la logic 0, the port pin is controlled by the corresponding bit in
the port SFR.
not used
The output of the PWM is a pulse of period 21.33 s with a pulse HIGH time determined
by the binary value of these 6-bits multiplied by 0.33 s. PV5 is the most significant bit.
PV5
5
PV4
4
9
PV3
3
DESCRIPTION
PV2
2
Preliminary specification
PV1
1
SAA5288
PV0
0