Daewoo DUB-2850GB Service Manual page 33

CP-780 Service Manual
4.7.2 Features
General features
-Targeted to provide a low cost solution for Set Top Box technology
-Comprehensive driver software and development tool support
-3.3 V and 1.2V power supplies
-Philips CMOS 0.12m process technology
-SQFP208 package
CPU related features
The pnx831x includes an embedded 32-bit MIPS RISC-based CPU which have the following
main features:
-32-bit PR1910 core operating at 120 MHz.
-MIPS-II ISA and MIPS16 instruction set
-Unified 8K Byte Instruction/Data cache
-4K Byte deeply embedded memory.
-Two 32-bit timers with compare and enable
-One 32 -bit watchdog timer with compare and a watchdog interrupt
-Copy-back store policy, write on allocate
-Debug Support Unit (DSU) with Enhanced JTAG interface version 2.0
DMA features
Thepnx831x has an integrated 4-channel high performance DMAC ontroller engine that can
Be used to perform a variety of tasks in the system.
-supports 4 DMA channels allowing transfer from any memory location or peripherals to any
memory location. The arbitration mechanism between the 4 channels is round-robin.
-Buffered mode DMA with a 16-byte data buffer.
-Transfer type programmable for source and target buffer (Byte, Half-word, Word, 4-Word
burst).
-Support for IO (non-incrementing addresses) source and/or destination.
-Configurable throttle support with throttle sizes ranging from 16 to 112 bytes.
-Integrated CRC Engine to perform CRC of MPEG section data as a post-process after the
section data has been collected into a memory queue.The CRCpolynomial is fixed and
is based on the 32-bit CRCdecoder model described in the Annex B of ISO/IEC 13818-1
specification.
Memory and bus interfaces
The pnx831x has two external buses:
-16-bit SDRAM memory interface which supports a scalable frequency up to 133 MHz. (64 Mbit,
128 Mbit, 256 Mbit)
-16-bit memory and peripheral interface to connect ROM, NOR Flash and various peripherals.
Peripheral interfaces
The pnx831x has many embedded peripheral units which have the following physical
interfaces:
-Two UART (RS-232) data ports: one with six wires for modem support and one with two wires
-Two I2C master / slave transceivers, supporting the standard (100 Kbit/s) and fast (400 Kbit/s)
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