A SERVICE OF

logo

2 - 6
Figure 2-3 PS Board Block Diagram
2.2 PS Board (OKIPAGE 6ex option)
The PS board consists of two Program & Font ROM's, DRAM's, an EEPROM, and a host interface
circuit.
(1) Program & Font ROM's
The Program & Font ROMs store the PostScript Level II program and its fonts. Mask ROM
is used for the Program & Font ROMs.
(2) DRAM
0.5MB of DRAM's reside on the PS board.
(3) EEPROM
4.096 bit-Electrically Erasable PROM (EEPROM) is mounted on the PS board for storing the
PostScript's menu settings.
(4) Local Talk I/F
Apple Talk protocol data is received from the host system via LocalTalk interface. The block
diagram is shown in Figure 2-3.
(5) SIMM Socket
One SIMM Socket is mounted on the PS board.
Program & Font
ROM
4MB Mask ROM
Resident RAM
(0.5MB)
SCC
85C30
LocalTalk I/F
(RS422 I/F)
EEPROM
(4K)
SIMM
Socket