ml670100 Oki Semiconductor, ml670100 Datasheet - Page 174

• Manufacturer Part Number: ml670100
• Description: Ml670100 Is A High-performance 32-bit Microcontroller
• Manufacturer: Oki Semiconductor

11.2.11
11-18
The Refresh Timing Control Register (RTCON) is an 8-bit read/write register that specifies the
RAS precharge time (t
3) back from self-refresh mode to normal operation mode.
After a system reset, this register contains 0x37.
Bit Descriptions
CHS
The CAS Hold Self-refresh (CHS) field specifies t
from self-refresh mode to normal operation mode. The range is from 1 clock cycle to 4.
RPS
The RAS Precharge Self-refresh (RPS) field specifies t
switching back from self-refresh mode to normal operation mode. The range is from 2 clock
cycles to 9.
Refresh Timing Control Register (RTCON)
7
0
6
0
Figure 11.13 : Refresh Timing Control Register (RTCON)
A "0” indicates a reserved bit. Always write "0” to it.
Writing "1” produces unreliable operation.
5
RPS
CHS
) and CAS hold time (t
4
3
0
2
CHS
CHS
RPS
) for switching the DRAM banks (2 and
1
, CAS hold time, for switching back
RPS
, the RAS precharge time, for
000
001
010
011
100
101
110
111
00
01
10
11
0
RAS precharge time, tRPS, = 2 clock cycles
RAS precharge time, tRPS, = 3 clock cycles
RAS precharge time, tRPS, = 4 clock cycles
RAS precharge time, tRPS, = 5 clock cycles
RAS precharge time, tRPS, = 6 clock cycles
RAS precharge time, tRPS, = 7 clock cycles
RAS precharge time, tRPS, = 8 clock cycles
RAS precharge time, tRPS, = 9 clock cycles
CAS hold time, tCHS, = 1 clock cycle
CAS hold time, tCHS, = 2 clock cycles
CAS hold time, tCHS, = 3 clock cycles
CAS hold time, tCHS, = 4clock cycles