saa5647hl NXP Semiconductors, saa5647hl Datasheet - Page 11

• Manufacturer Part Number: saa5647hl
• Description: Saa56xx Enhanced Tv Microcontrollers With On-screen Display Osd
• Manufacturer: NXP Semiconductors

Philips Semiconductors
8.2
SAA56xx devices have a set of security bits allied with
each section of the device, i.e. Program ROM, Character
ROM and Packet 26 ROM. The security bits are used to
prevent the ROM from being overwritten once
programmed, and also the contents being verified once
programmed.
2004 Sep 03
handbook, full pagewidth
handbook, full pagewidth
Enhanced TV microcontrollers with
On-Screen Display (OSD)
ROM protection and verification
MEMORY
MEMORY
PROGRAM ROM
(128 or 192 kbytes)
CHARACTER ROM
(12 kbytes)
PACKET 26 ROM
(4 kbytes)
PROGRAM ROM
(128 OR 192 kbytes)
CHARACTER ROM
(12 kbytes)
PACKET 26 ROM
(4 kbytes)
Fig.4 Security bits for production programmed devices.
Fig.5 Security bits for production blank devices.
11
SECURITY BITS SET
SECURITY BITS SET
USER ROM PROGRAMMING
USER ROM PROGRAMMING
The security bits can be programmed once only and
cannot be erased.
The SAA56xx security bits are set as shown in Fig.4 for
production programmed devices and are set as shown in
Fig.5 for production blank devices.
DISABLED
DISABLED
DISABLED
ENABLED
ENABLED
ENABLED
ENABLED
ENABLED
ENABLED
ENABLED
ENABLED
ENABLED
VERIFY
VERIFY
GSA036
GSA037
Product specification
SAA56xx