CHAPTER 2 PIN FUNCTIONS
44
User’s Manual U14359EJ4V0UM
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Pin Name
I/O
Function
Alternate Function
LCAS
Output
Column address strobe signal output for DRAM lower data
PCT0/LWR/LDQM
UCAS
Output
Column address strobe signal output for DRAM higher data
PCT1/UWR/UDQM
LWR
Output
External data lower byte write strobe signal output
PCT0/LCAS/LDQM
UWR
Output
External data higher byte write strobe signal output
PCT1/UCAS/UDQM
LDQM
Output
Output disable/write mask signal output for SDRAM lower data
PCT0/LCAS/LWR
UDQM
Output
Output disable/write mask signal output for SDRAM higher data
PCT1/UCAS/UWR
RD
Output
External data bus read strobe signal output
PCT4
WE
Output
Write enable signal output for DRAM
PCT5
OE
Output
Output enable signal output for DRAM
PCT6
BCYST
Output
Strobe signal output that shows the start of the bus cycle
PCT7
CS0
PCS0
CS1
PCS1/RAS1
CS2
PCS2/IOWR
CS3
PCS3/RAS3
CS4
PCS4/RAS4
CS5
PCS5/IORD
CS6
PCS6/RAS6
CS7
Output
Chip select signal output
PCS7
RAS1
PCS1/CS1
RAS3
PCS3/CS3
RAS4
PCS4/CS4
RAS6
Output
Row address strobe signal output for DRAM
PCS6/CS6
IOWR
Output
DMA write strobe signal output
PCS2/CS2
IORD
Output
DMA read strobe signal output
PCS5/CS5
SDCKE
Output
SDRAM clock enable signal output
PCD0
SDCLK
Output
SDRAM clock signal output
PCD1
SDCAS
Output
Column address strobe signal output for SDRAM
PCD2/LBE
SDRAS
Output
Row address strobe signal output for SDRAM
PCD3/UBE
LBE
Output
External data bus lower byte enable signal output
PCD2/SDCAS
UBE
Output
External data bus higher byte enable signal output
PCD3/SDRAS
D0 to D15
I/O
16-bit data bus for external memory
PDL0 to PDL15
A0 to A15
PAL0 to PAL15
A16 to A25
Output
26-bit address bus for external memory
PAH0 to PAH9
RESET
Input
System reset input
−
X1
Input
−
X2
−
Connects the crystal resonator for system clock oscillation. In the
case of an external source supplying the clock, it is input to X1.
−
CLKOUT
Output
System clock output
PCM1/BUSCLK
BUSCLK
Output
Bus clock output
PCM1/CLKOUT