
External Bus Interface (EBI)
MPC5644A Microcontroller Reference Manual, Rev. 6
318
Freescale Semiconductor
between the accesses unless that access is the end of a 64-bit boundary. In this case, an extra cycle is
required between TA and the next TS in order to get the next 64-bits of write data internally and RD_WR
negates during this extra cycle.
Figure 14-28. 32-Byte Write Cycle with External TA, Basic Timing
14.5.2.6.3
Small access example #3: 32-byte read to 32-bit port with BL=1
shows an example of a 32-byte read to a 32-bit burst enabled port with burst length of 4
words, requiring two 16-byte external transactions. For this case, the address for the 2nd 4-word burst
access is calculated by adding 0x10 to the lower 5 bits of the 1st address (no carry), and then masking out
the lower 4 bits to fix them at zero.
Table 14-14. Examples of 4-word Burst Addresses
1st Address
Lower 5 bits of 1st A
0x10 (no carry)
Final 2nd Address (After
Masking Lower 4 Bits)
0x000
0x10
0x10
0x008
0x18
0x10
0x010
0x00
0x00
0x018
0x08
0x00
0x020
0x30
0x30
0x028
0x38
0x30
0x030
0x20
0x20
0x038
0x28
0x20
DATA is valid
DATA is valid
CLKOUT
ADDR[3:31]
TS
TA
RD_WR
BDIP
WE
CS[
n
]
A
A + 4
A + 8
A + 0xc
DATA is valid
This extra cycle is required after accesses 2, 4, and 6 to get the next 64-bits of internal write data.
*
Four more external accesses (not shown) are required to complete the internal 32-byte request.
The timing of these is the same as accesses 1-4 shown in this diagram.
**
1
2
3
4**
*
DATA[0:31]
Содержание MPC5644A
Страница 2: ...MPC5644A Microcontroller Reference Manual Rev 6 2 Freescale Semiconductor...
Страница 24: ...MPC5644A Microcontroller Reference Manual Rev 6 24 Freescale Semiconductor...
Страница 26: ...MPC5644A Microcontroller Reference Manual Rev 6 26 Freescale Semiconductor...
Страница 52: ...Introduction MPC5644A Microcontroller Reference Manual Rev 6 52 Freescale Semiconductor...
Страница 56: ...Memory Map MPC5644A Microcontroller Reference Manual Rev 6 56 Freescale Semiconductor...
Страница 130: ...Device Performance Optimization MPC5644A Microcontroller Reference Manual Rev 6 130 Freescale Semiconductor...
Страница 204: ...Multi Layer AHB Crossbar Switch XBAR MPC5644A Microcontroller Reference Manual Rev 6 204 Freescale Semiconductor...
Страница 212: ...Peripheral Bridge PBRIDGE MPC5644A Microcontroller Reference Manual Rev 6 212 Freescale Semiconductor...
Страница 558: ...System Integration Unit SIU MPC5644A Microcontroller Reference Manual Rev 6 558 Freescale Semiconductor...
Страница 582: ...Frequency modulated phase locked loop FMPLL MPC5644A Microcontroller Reference Manual Rev 6 582 Freescale Semiconductor...
Страница 766: ...Enhanced Time Processing Unit eTPU2 MPC5644A Microcontroller Reference Manual Rev 6 766 Freescale Semiconductor...
Страница 1228: ...Decimation Filter MPC5644A Microcontroller Reference Manual Rev 6 1228 Freescale Semiconductor...
Страница 1236: ...System Information Module and Trim SIM MPC5644A Microcontroller Reference Manual Rev 6 1236 Freescale Semiconductor...
Страница 1250: ...Cyclic Redundancy Checker CRC Unit MPC5644A Microcontroller Reference Manual Rev 6 1250 Freescale Semiconductor...
Страница 1336: ...Deserial Serial Peripheral Interface DSPI MPC5644A Microcontroller Reference Manual Rev 6 1336 Freescale Semiconductor...
Страница 1388: ...Enhanced Serial Communication Interface ESCI MPC5644A Microcontroller Reference Manual Rev 6 1388 Freescale Semiconductor...
Страница 1440: ...FlexCAN Module MPC5644A Microcontroller Reference Manual Rev 6 1440 Freescale Semiconductor...
Страница 1624: ...FlexRay Communication Controller FlexRay MPC5644A Microcontroller Reference Manual Rev 6 1624 Freescale Semiconductor...
Страница 1670: ...JTAG Controller JTAGC MPC5644A Microcontroller Reference Manual Rev 6 1670 Freescale Semiconductor...
Страница 1692: ...Nexus Port Controller NPC MPC5644A Microcontroller Reference Manual Rev 6 1692 Freescale Semiconductor...
Страница 1701: ...Development Trigger Semaphore DTS MPC5644A Microcontroller Reference Manual Rev 6 Freescale Semiconductor 1701...
Страница 1702: ...Development Trigger Semaphore DTS MPC5644A Microcontroller Reference Manual Rev 6 1702 Freescale Semiconductor...