Mbyte Rom System Including Parity Paths To Dram—64-Bit Mode - Motorola MPC8240 User Manual

ROM/Flash Interface Operation
MDH[0:31]
MDL[0:31]
PAR[0:7]
SDMA[12:0]
SDBA[0]
Buffers
RCS[0]
RCS[1]
MPC8240
Address
Signals
(Outputs)
Logical Names
Notes:
1. The array of ROM memory devices are 8-Mbit (1M x 8 or 512K x 16) configured for 1M x 8 operation.
2. A[-1] is the lsb of the ROM memory devices.
3. BHE connected to GND enables A[-1] as an input and sets Q[15:8] to Hi-Z.
4. Q[7:0] of the ROM Memory devices are data outputs connected to MDH[0-31] and MDL[0:31].
MDH[0:7] is the most significant byte lane and MDL[24:31] is the least significant byte lane.
5. All OE and BHE signals are connected to GND.
6. RCS0 is connected to all CE in Bank 0 (8 Mbytes) and RCS1 is connected to all CE in Bank 1 (8 Mbytes).
Figure 6-50. 16-Mbyte ROM System Including Parity Paths to DRAM—64-Bit Mode
6-74
Data Path to/from DRAM/SDRAM Array
Parity Path to/from DRAM/SDRAM Array
Address Path to DRAM/SDRAM Array
1Mx8 ROM
2Mx8 SDRAM
A[0:18]
2Mx8 SDRAM
A[-1]
A[0-11]
2Mx8 SDRAM
BA[0-1]
A(11-0)
Q[15:8]
RAS
2Mx8 SDRAM
BA(1-0)
A(11-0)
Q[7:0]
CAS
RAS
2Mx8 SDRAM
BA(1-0)
A[0-11]
WE DQ[0-7]
CAS
RAS
2Mx8 SDRAM
CE BA[0-1]
A[0-11]
CKE
WE DQ(7-0)
CAS
RAS
2Mx8 SDRAM
BA[0-1]
OE
A[0-11]
CLK
CKE
WE DQ(7-0)
CAS
RAS
BA[0-1]
BHE
A[0-11]
CS
CLK
CKE
WE DQ[0-7]
CAS
RAS
BA[0-1]
BHE
CS
CLK
CKE
WE DQ[0-7]
CAS
RAS
GND
BHE
CS
CLK
CKE
WE DQ[0-7]
CAS
BHE
CS
CLK
CKE
WE DQ[0-7]
BHE
CS
CLK
CKE
BHE
CS
CLK
BHE
CS
BHE
PAR
0 1 2 3 4 5 6
msb
1 1 1 1 1 1 1
9 8 7 6 5 4 3
MPC8240 Integrated Processor User's Manual
1Mx8 ROM
2Mx8 SDRAM
A[0:18]
2Mx8 SDRAM
A[-1]
A[0-11]
2Mx8 SDRAM
BA[0-1]
A(11-0)
NC
RAS
2Mx8 SDRAM
BA(1-0)
MDH[0:7] A(11-0)
CAS
RAS
BA(1-0)
MDH[8:15] A[0-11]
WE
CAS
RAS
CE BA[0-1]
MDH[16:23]
CKE
WE
CAS
RAS
OE
MDH[24:31]
CLK
CKE
WE
CAS
MDL[0:7] BHE
CS
CLK
CKE
WE
MDL[8:15]
BHE
CS
CLK
CKE
MDL[16:23] GND BHE
CS
CLK
MDL[24:31] BHE
CS
BHE
BHE
SDBA
7 0 1 9 8 7
0
AR
1 11 1 9 8 7
2 0
Q[15:8] NC
MDH[0:7]
Q[7:0]
2Mx8 SDRAM
MDH[8:15]
DQ[0-7]
2Mx8 SDRAM
A[0-11] MDH[16:23]
DQ(7-0)
2Mx8 SDRAM
BA[0-1]
A[0-11] MDH[24:31]
DQ(7-0)
RAS
BA[0-1]
A[0-11] MDL[0:7]
DQ[0-7]
CAS
RAS
BA[0-1]
MDL[8:15]
WE DQ[0-7]
CAS
RAS
MDL[16:23]
CKE
WE DQ[0-7]
CAS
MDL[24:31]
CLK
CKE
WE DQ[0-7]
CS
CLK
CKE
CS
CLK
BHE
CS
BHE
SDMA
6 5 4 3 2 1
lsb
6 5 4 3 2 1
0
0