Rice Lake Motorola DS457 Laser Scanner - Manual (Page 24)

1 - 4 DS457 Fixed Mount Imager Integration Guide
DS457 Decoder/Interface Board
Marvell PXA320 Processor
The digital system is built on a Marvell PXA320 (Intel XScale ® ) super-pipelined RISC microarchitecture core.
The major features of the core are:
•
CPU clock speed up to 624 MHz with external DDR SDRAM bus speed of 133 MHz.
• 32 KB instruction/32 KB data L1 cache, 256 KB unified L2 cache, 728 KB internal SRAM
Power Management
The DS457 decoder/interface board has various power management options depending on the host interface.
• USB (SNAPI, USB HID Keyboard, etc.)
- The DS457 automatically manages its power usage, including
USB suspend mode. Additionally, when drawing power from the USB bus, the DS457 does not exceed
the USB limit of 500 mA.
• SSI or RS-232
- When using SSI or any RS-232 host interface, the DS457 uses one of the following power
modes. See
Power Mode (RS-232 Hosts Only) on page 6-15
.
•
Continuous Power: The DS457 is fully awake and running, even when not in a decode session.
•
Low Power (default): The DS457 draws less current at idle than when in Continuous Power mode.