Xerox Phaser 3250 Service Manual page 78

Phaser 3250 Laser Printer Service Manual
Engine Controller
Laser Unit interface
Step Motor: 2 channels
PWM: 8 channels
ADC: 6 channels
I2C Controller
I2C (S-BUS) Slave Device Support (I2C version 2.1)
RTC
RTC Core Voltage: 3 V
PLL
3 PLL: Main, PCI, PVC
Memory
The Main Controller Board has Flash ROM and DRAM memory units.
Flash Memory: Stores System Program and downloads the System
Program through PC Interface.
Capacity: 16 MB (NOR Flash)
Random Access Time: 10 us (max.)
Serial Page Access Time: 50 ns (min.)
DRAM: It is used as Swath Buffer, System Working Memory Area, while
printing. DRAM also stores Font List, compresses into Flash memory on
DRAM, and uses it as PCL font for export based on printer configuration.
Capacity: 32 MB (basic), up to 160 MB (factory option)
Type: SDRAM 100 MHz/133 MHz, 32 Bit
RAM DIMM
Theory of Operation
2-15