HD6433044 Hitachi Semiconductor, HD6433044 Datasheet - Page 163

• Manufacturer Part Number: HD6433044
• Description: (HD64 Series) Hitachi Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

7.1.3 Input/Output Pins
Table 7-1 summarizes the refresh controller’s input/output pins.
Table 7-1 Refresh Controller Pins
Pin
RFSH
HWR
LWR
RD
CS
7.1.4 Register Configuration
Table 7-2 summarizes the refresh controller’s registers.
Table 7-2 Refresh Controller Registers
Address*
H'FFAC
H'FFAD
H'FFAE
H'FFAF
Note: * Lower 16 bits of the address.
3
Name
Refresh
Upper write/upper column
address strobe
Lower write/lower column
address strobe
Column address strobe/
write enable
Row address strobe
Name
Refresh control register
Refresh timer control/status register
Refresh timer counter
Refresh time constant register
Signal
Abbr.
RFSH
UW/UCAS
LW/LCAS
CAS/WE
RAS
149
Output
Output
Output
I/O
Output
Output
Abbreviation
RFSHCR
RTMCSR
RTCNT
RTCOR
Function
Goes low during refresh cycles; used
to refresh DRAM and PSRAM
Connects to the UW pin of 2WE
DRAM or UCAS pin of 2CAS DRAM
Connects to the LW pin of 2WE DRAM
or LCAS pin of 2CAS DRAM
Connects to the CAS pin of 2WE
DRAM or WE pin of 2CAS DRAM
Connects to the RAS pin of DRAM
R/W
R/W
R/W
R/W
R/W
Initial Value
H'02
H'07
H'00
H'FF