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Workstation 5 Field Service Guide
Workstation 5 System Board Technical Descriptions
CS5536 Companion Device
CS5536 Companion Device
REF: ABRD88 - Sheets 8, 9 and 10
The CS5536 Companion Device is designed to work with the LX800, a
processor with an integrated memory controller. Together, the LX800
processor and CS5536 Companion Device provide a low power, high
performance embedded solution for both the Workstation 4 LX and the
Workstation 5.
The internal architecture is based on the high-performance GeodeLink
architecture that yields high internal speed (over 4 GB/s) data movement and
versatile power management.
Communications with the AMD LX800 processor is over the 66Mhz PCI Bus.
The Geode Companion device includes many IO functions on-chip. These
include:
System Management Bus (SMB) Controller
The SMB is a two-wire synchronous serial interface compatible with the
System Management Bus physical layer. On the WS5 system board, the
SMB controller in the Companion Device is connected to Ethernet
Controller U22, as well as each DDR DIMM socket.
Serial Interface
The CS5536 includes two high-speed industry standard serial ports,
configured to support the Customer Display and IDN Interfaces. The
UARTs are 16550 and 16450 software compliant and support baud rates up
to 115.2 kbps.
Real Time Clock (RTC) and CMOS RAM
The companion device contains the equivalent of Motorola MC146818A
compatible real time clock. The clock performs two functions. It keeps
track of the time and date when the system is not connected to AC power,
and provides 242 bytes of non-volatile memory for storing BIOS and
system data.
The clock contains separate registers for seconds, minutes, hours, days
(both day of week and day of month), months, and years. The RTC
operates from a 32.768 Khz crystal and is powered from a 3V lithium
battery that can maintain operation for several years.
ATA Interface
The IDE Interface is an ATA-5 specification compatible IDE controller
(ATAC). Two devices are supported, using PIO Modes 0 through 4,
MDMA modes 0 to 2, and UDMA/66 mode 0 through 4.
