4-50
Memory Controller
4.9.2.2 RWD - Bank Active Watchdog Timer
Address Offset: x2C
Width:
32
Reset Value: xFF00_0000
Access: Read/Write
This register limits the maximum internal bank active time for SDRAM. This register represents the maxi-
mum amount of time in units of eight processor bus clock cycles.
4.9.2.3 RTR - Refresh Timer Register
Address Offset: x30
Width:
32
Reset Value: x03F8_0000
Access: Read/Write
The 16 bit field of this register determines the memory refresh rate for SDRAM. The internal counter runs
at the processor bus frequency, thus at 66 MHz (15ns cycle time), a value of 0x03F8 (1016 decimal) pro-
duces a refresh interval of 15.24 us (1016 x 15ns = 15.24us). This register may be programmed to accom-
modate other clock frequencies.
Bit
Name
Reset
Value
Description
0:7
RASWDT
1s
Bank Active Watchdog timer value.
8:31
0s
Reserved
Bit
Name
Reset
Value
Description
0:3
-
0s
Hardcoded to Zero
4:12
RTINTVL
Programmable
13:15
-
0s
Hardcoded to Zero
16:31
0s
Reserved - Hardcoded to Zero.
Summary of Contents for CPC700
Page 10: ...Table of Contents x Table of Contents...
Page 16: ...Tables xvi List of Tables...
Page 28: ...1 12 CPC700 User s Manual Preliminary...
Page 72: ...3 36 Processor Interface...
Page 132: ...4 60 Memory Controller...
Page 184: ...5 52 PCI Interface...
Page 194: ...6 10 Clock Power Management and Reset...
Page 224: ...8 18 IIC...
Page 244: ...10 10 Interrupt Controller...
Page 246: ...I 11 2 JTAG...
Page 250: ...12 4 Processor Local Bus PLB...
Page 262: ...14 10 Register Summary...
Page 267: ...CPC700 User s Manual Preliminary...