Ampro Corporation Single Board Computer Littleboard 550 - Manual (Page 28)

Chapter 3 Hardware
22 Reference Manual LittleBoard 550
CPU (U1)
The LittleBoard 550 offers three VIA Technologies Eden processor choices; high performance 1GHz
ESP 10000 processor, 533MHz ESP 5000 processor, or the low cost, 300MHz ESP3000 processor.
ESP Processors
The ESP (0.13 µ or 0.15µ) processors at 1GHz, 533MHz, or 300MHz use 133MHz, 133MHz, or 66MHz
FSB (front side bus) respectively, with 128kB Level 1 cache and 64kB Level 2 cache. The ESP
processors require a heatsink, but no fan.
NOTE A CPU fan connector is provided for your convenience to
accommodate any special requirements. See Table 3-28.
Memory
The LittleBoard 550 memory consists of the following elements:
• SDRAM
• Flash memory
• Serial EEPROM (SEEP)
SDRAM Memory (DIMM1)
The LittleBoard 550 supports a single standard 168-pin DIMM slot.
• DIMM slot can support up to 2GB of memory
• Supports PC 133 (133MHz, 7.5ns) and PC 100 (100MHz, 10ns)
• +3.3V SDRAM
NOTE Ampro recommends using only PC 133 (133MHz), 3.3V, 7.5ns, 168-
pin, SDRAM DIMM, but PC 100 (100MHz, 10ns) will function. PC
133 provides the best performance for the Eden processors.
Flash Memory (U17)
There is an 8-bit wide, 512kB flash device used for system BIOS that is connected to the Southbridge,
VT82C686B, through an ISA bus transceiver. The BIOS is re-programmable and the supported features
are detailed in Chapter 4, BIOS Setup.
Serial EEPROM (SEEP)
The 2-wire Serial EEPROM (SEEP) contains 4k-bits and at least 512-bit area is reserved for the user.
The SEEP is used to store system parameters for battery-free boot capability when there is no battery
present. The SEEP uses the SMBus as its 2-wire interface.