Oki OL1200, Руководство по обслуживанию, Страница: 20 / 272

System area Working area used for the
program Fixed
Working
area used
for the
program Fixed
Raster buffer Stores converted bit image data Enable Expandable
Receive buffer Stores temporarily the data
received from the host interface Enable Expandable
Page buffer Adds print information to the
analyzed receive data and stores
the resulted data. Expandable
DLL/macro
buffer Stores soft fonts and macro data. Expandable
Font cache
buffer Stores bit map fonts generated
by the font rasterizer based on
scalable font information Enable Expandable
(4) EEPROM
The EEPROM has a 4-kbit capacity and stores the following data.
- Menu data
- Various counter data (page counter, drum counter, fuser counter, etc.)
- Adjustment parameters (LED head drive time, print start position, etc.)
(5) LSI (MSM10S0050-015GS)
This LSI is connected to the CPU via the bus as a peripheral device of the CPU and controls the memory
based on the RAS signal and address signal received from the CPU.
(6) LSI (MBCE31701-040FP-BND)
This LSI is used as a peripheral device of the CPU and performs smoothing compensation (OST) of print
image data (300 dpi and 600 dpi). In addition, it transfers serially bit image data for each dot line to the
LED head.
(7) Host interface
This printer has the following interfaces to the host.
- Centronics bidirectional parallel interface
- RS232C serial interface
- OKI HSP interface (Option)
The single effective interface or the automatic interface select mode can be selected using the menu. If
the busy state of the printer continues for a long time period, the buffer near-full control releases the busy
status at constant intervals even if the host side is busy so not to cause the interface time-out at the host
side.
(a) Centronics bidirectional parallel interface
This is an interface conforming to IEEE-1284 and provides either unidirectional or bidirectional
communications according to each of the following communication modes.
- Compatibility mode
- Unidirectional communications from the host to the printer.
- Nibble mode
This mode transmits 4-bit wide data from the printer to the host. In this mode, each 1-byte data is