4-12
Memory Controller
# Column address bit 10 sent out on M11 for 13 x 11 (4) parts.
4.5.6 Precharge Command
Issuing the Precharge Command instructs the SDRAM to precharge all banks and is generated by the
SDRAM controller as needed when Auto-Precharge is disabled as configured by register bit SD_APGE.
The memory address bus contains the command associated with the precharge cycle and is formatted as
follows:
Note: Shaded entries are “don’t care” and will be driven with a stable value for every clock cycle.
4.5.7 Refresh
Refresh of odd memory banks is staggered from the refresh of even memory banks. Only banks enabled in
the Memory Bank Enable register will be initialized following reset and refreshed during normal operation.
Refresh requests are generated internally when the refresh timer expires. The Refresh interval is program-
mable via the RTR register in the Global Memory Timing Registers. During refresh, all SDRAM and ROM
accesses are delayed until the current or pending refresh cycle completes.
Note: During refresh, MA(12:0) are not required and will contain the last address driven to memory.
Mode 3
13 x 11 (4)
BA
1
BA
0
MA
12
MA
11
MA
10/
AP
MA
9
MA
8
MA
7
MA
6
MA
5
MA
4
MA
3
MA
2
MA
1
MA
0
Row
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
A16
A17
A18
A19
Column
A5
A6
A6
A3#
AP
A4
A20
A21
A22
A23
A24
A25
A26
A27
A28
Mode 4
12 x 8 (4)
13 x 8 (2)
12 x 8 (4)
BA
1
BA
0
MA
12
MA
11
MA
10/
AP
MA
9
MA
8
MA
7
MA
6
MA
5
MA
4
MA
3
MA
2
MA
1
MA
0
Row
A7
A20
A7
A8
A9
A10
A11
A12
A13
A14
A15
A16
A17
A18
A19
Column
A7
A20
A7
A3
AP
A5
A20
A21
A22
A23
A24
A25
A26
A27
A28
Addressing
Mode
Mode 1,2,3
(ALL)
BA
1
BA
0
MA
12
MA
11
MA
10/
AP
MA
9
MA
8
MA
7
MA
6
MA
5
MA
4
MA
3
MA
2
MA
1
MA
0
Precharge
b’1’
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...