II CORE BLOCK: BCU (Bus Control Unit)
Refresh RPC delay
Use RPC0 to set the RPC delay value of a refresh cycle (a delay time from the immediately preceding precharge to the fall of #CAS).
RPC0 = "1": 2 cycles
RPC0 = "0": 1 cycle
Refresh RAS pulse width
Use RRA to set the #RAS pulse width of a
Table 4.17 Refresh RAS Pulse Width
RRA1 | RRA0 | Pulse width |
1 | 1 | 5 cycles |
1 | 0 | 4 cycles |
0 | 1 | 3 cycles |
0 | 0 | 2 cycles |
The initial default value is 2 cycles.
Number of RAS precharge cycles
Use RPRC to choose the number of RAS precharge cycles.
Table 4.18 Number of RAS Precharge Cycles
RPRC1 | RPRC0 | Number of cycles |
1 | 1 | 4 cycles |
1 | 0 | 3 cycles |
0 | 1 | 2 cycles |
0 | 0 | 1 cycle |
The initial default value is 1 cycle.
CAS cycle control
Use CASC to choose the number of CAS cycles when accessing DRAM.
Table 4.19 Number of CAS Cycles
CASC1 | CASC0 | Number of cycles |
1 | 1 | 4 cycles |
1 | 0 | 3 cycles |
0 | 1 | 2 cycles |
0 | 0 | 1 cycle |
The initial default value is 1 cycle.
RAS cycle control
Use RASC to choose the number of RAS cycles when accessing DRAM.
Table 4.20 Number of RAS Cycles
RASC1 | RASC0 | Number of cycles |
1 | 1 | 4 cycles |
1 | 0 | 3 cycles |
0 | 1 | 2 cycles |
0 | 0 | 1 cycle |
The initial default value is 1 cycle.
EPSON | S1C33210 FUNCTION PART |