saa5547ps NXP Semiconductors, saa5547ps Datasheet - Page 37

• Manufacturer Part Number: saa5547ps
• Description: Saa550x; Saa554x Tv Microcontrollers With Closed Captioning Cc And On-screen Display Osd
• Manufacturer: NXP Semiconductors

Philips Semiconductors
15 I
The I
serial clock (SCL) line. The definition of the I
protocol can be found in the document “The I
how to use it (including specification) ”. This document may
be ordered using the code 9398 393 40011.
The device operates in four modes:
The microcontroller peripheral is controlled by the Serial
Control SFR (S1CON) and its status is indicated by the
Status SFR (S1STA). Information is transmitted/received
to/from the I
Slave Address SFR (S1ADR) is used to configure the
slave address of the peripheral.
The byte level I
serial port on the P8xCE558, except for the clock rate
selection bits CR<2:0> in S1CON. The operation of the
subsystem is described in detail in the “P8xCE558 data
sheet” .
15.1
Two I
SCL1/SDA1. The selection of the port is done using
TXT21.I
port is enabled, any information transmitted from the
device goes onto the enabled port. Any information
transmitted to the device can only be acted on if the port is
enabled.
If both ports are enabled then data transmitted from the
device is seen on both ports, however data transmitted to
the device on one port can not be seen on the other port.
16 MEMORY INTERFACE
The memory interface controls access to the embedded
DRAM, refreshing of the DRAM and page clearing.
The DRAM is shared between Data Capture, display and
microcontroller sections.
The Data Capture section uses the DRAM to store
acquired information that has been requested. The display
reads from the DRAM information and converts it into RGB
values. The microcontroller uses the DRAM as embedded
auxiliary RAM.
2000 Feb 23
Master transmitter
Master receiver
Slave transmitter
Slave receiver.
TV microcontrollers with Closed Captioning (CC)
and On-Screen Display (OSD)
2
2
2
C-BUS SERIAL I/O
C-bus consists of a serial data (SDA) line and a
C-bus ports are available SCL0/SDA0 and
I
2
2
C-bus port selection
C PORT 0 and TXT21.I
2
C-bus using the Data SFR (S1DAT) and the
2
C-bus serial port is identical to the I
2
C PORT 1. When the
2
2
C-bus
C-bus and
2
C-bus
37
16.1
The memory is partitioned into two distinct areas, the
dedicated Auxiliary RAM area, and the Display RAM area.
The Display RAM area when not being used for Data
Capture or Display can be used as an extension to the
auxiliary RAM area.
16.1.1
The Auxiliary RAM is not initialised at power-up.
Application software must initialize this Auxiliary RAM. The
contents of the Auxiliary RAM area, and the Display RAM
are maintained during Standby and Idle modes, but are
lost if Power-down mode is entered.
16.1.2
The Display RAM (Block 0 only) is initialised on power-up
to a value of 20H. The contents of the Display RAM are
maintained when entering Idle mode. If Idle mode is exited
using an interrupt then the contents are unchanged, if Idle
mode is exited using a reset then the contents are
re-initialised to 20H.
Full Closed Caption display requires a display RAM from
8000H to 845FH. The memory from 8460H to 84FFH
(must be initialized by the application software) can be
utilized as an extension to the dedicated contiguous
Auxiliary RAM that occupies 000H to 02FFH.
16.2
The dedicated Auxiliary RAM area occupies 0.75 kbytes,
with an address range from 0000H to 02FFH. The Display
RAM occupies 1.25 kbytes with an address range from
2000H to 24FFH for TXT mode and 8000H to 84FFH for
CC mode. The two modes although having different
address ranges occupy the same physical DRAM area.
The hardware will only initialize 1-kbyte (block 0) of the
available 1.25 kbytes on the device. The application
software must initialize this additional 0.25 kbytes if it is to
be used as display RAM or auxiliary RAM.
Memory structure
Memory mapping
A
D
UXILIARY
ISPLAY
RAM
RAM
Preliminary specification
SAA55xx