DSP 104-plus, Reference Manual

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14 158004.B00
(ball grid array) device on the main printed circuit board. The CS5530A contains
graphics processing logic, the IDE and USB ports, clock generators, ISA bus
interface and the peripheral devices traditionally implemented in a motherboard chip
set. (Earlier versions of the TP400 used the CX5530A, which has the same
functionality).
These peripherals include two 8237 compatible DMA control units (7 channels), one
8254 compatible timer control unit (3 channels) and two 8259 compatible interrupt
control units (15 interrupts). The majority of the peripheral functions are the same on
all PC compatible computers. This includes the timers, interrupt controllers and DMA
controllers as well as registers such as the NMI and speaker inhibit registers, fast
reset and A20 gate registers. Software that accesses desktop PC peripherals will
have the same effect when running on the TP400, giving rise to a high degree of
PC-compatibility.
The other housekeeping functions provided by the CS5530A are:
•
PCI to ISA bus bridge.
•
ISA bus memory and I/O address decoding logic.
•
Power management.
•
Game port (unused on the TP400).
•
MPEG playback hardware assist circuitry
The Geode GX1 and CS5530A chips also include a number of internal configuration
registers. These registers are unique to the Geode GX1 chip set. They control timing
on the expansion bus, shadow RAM, SDRAM configuration, memory mapping and so
forth. They are initialized by the BIOS and will not normally need to be accessed by
the user.
The performance of the TP400 may be gauged by the processor performance ratings
produced by the Norton SI program as shown in Table 1. This table also gives typical
power consumption figures for the TP400. At the time of writing the BIOS does not
support operation at 133MHz. The board will run at 333MHz, but the processor is not
rated to operate at this speed, so the 333MHz entry is for reference only.
The TP400 offers very low power consumption for a board of its performance. One
power measurement has been made with the graphics disabled – as can be seen
power consumption is significantly reduced with the graphics disabled. There is a
small increase of power as the graphics resolution increases, and a further small
increase when the PanelLink interface is used.
CPU
FREQUENCY NORTON
RATING TYPICAL
POWER
CONSUMPTION POWER WITH
GRAPHICS OFF
133MHz N/A N/A -
166MHz 317 670mA -
200MHz 387 700mA -
233MHz 456 820mA -
266MHz 526 870mA -
300MHz 595 1.03A 810mA
333MHz 663 1.09A -
TABLE 1 - TP400 PERFORMANCE RATINGS