Service manual

Samsung Electronics 5-5
As KS32C6200 has DRAM controller in it, DRAM can be connected with external memory. The control mode
of DRAM controller enabling EARLY WRITE, NORMAL READ, PAGE MODE, and BYTE/HALF WORD
ACCESS supports EDO DRAM as well as normal DRAM. DRAM READ/WRITE signals are /RD and /WR
signals used to control system buses. It supports CAS BEFORE RAS for DRAM REFRESH and self-refresh
mode for DRAM backup. Connected with common /LCAS, /UCAS and RAS[1:0], it consists of 2 banks.
Though each may be connected with up to 1M - 4M halfword, 512 Kbytes or 2 Mbytes are connected accord-
ing to the model for this product.
5-1-2-6. PARALLEL PORT INTERFACE
This part connected with the computer through the centronics connector makes possible parallel interface
with the computer. Data is transmitted according to the standard of IEEE P1284. This MFP controller supports
compatibility mode the traditional way to transmit print data, nibble mode (4bit data) to upload data to the
computer, and duplex high-speed transmission with the computer ECP(Extended Capabilities Port: 8bit data
transmission) all together.
It enables PC data to be printed and scanned data to be uploaded quickly to the computer. Besides, various
data transmission and reception with the computer such as uploading received fax data, downloading fax
data to be sent, and monitoring system control signals and system conditions are carried out here.
5-1-2-5. DRAM CONTROLLER
PPD(7 : 0)
DATA
BUSY
nSTROBE
nACK
Fig.5-1-5 Compatibility Hardware handshaking Timing