External Bus Interface (EBI)
MPC5565 Microcontroller Reference Manual, Rev. 1.0
Freescale Semiconductor
12-21
12.4
Functional Description
12.4.1
External Bus Interface Features
12.4.1.1
32-Bit Address Bus
The 324 BGA packaged devices have 20 address lines pinned out externally (24 bits available if CS[0:3]
are configured as ADDR[8:11]. Refer to the Pad Configuration Register.) A full 32-bit internal decode
determines whether the transaction target asserts a chip select pin.
12.4.1.2
32-Bit Data Bus
The entire 32-bit data bus is available for both external memory accesses and transactions involving an
external master in the 416 and 496BGA packaged devices.
In the 324 BGA package, the data bus is 16 bits.
12.4.1.3
16-Bit Data Bus
A 16-bit data bus mode is available via the DBM bit in EBI_MCR. Refer to
Section 12.1.4.5, “16-Bit Data
.”
12.4.1.4
Support for External Master Accesses to Internal Addresses
The EBI allows an external master to access internal address space when the EBI is configured for external
master mode in the EBI_MCR. External master operations are described in detail in
“Bus Operation in External Master Mode
.”
28
Reserved.
29–30
BSCY
[0:1]
Burst beats length in clocks. This field determines the number of wait states (external bus cycles) inserted in all burst
beats except the first, when the memory controller starts handling the external memory access and thus is using
SCY[0:3] to determine the length of the first beat.
• Total memory access length for each beat:
• Total cycle length (including the TS cycle):
Note:
The number of beats (4, 8, 16) is determined by BL and PS bits in the base register.
00 0-clock cycle wait states (1 clock per data beat)
01 1-clock cycle wait states (2 clocks per data beat)
10 2-clock cycle wait states (3 clocks per data beat)
11 3-clock cycle wait states (4 clocks per data beat)
Table 12-11. EBI_OR
n
and EBI_CAL_OR
n
Field Descriptions
(continued)
Field
Description
(1 + BSCY) External Clock Cycles
(2 + SCY) + [(Number of Beats – 1) x (BSCY + 1)]
Summary of Contents for MPC5565
Page 18: ...MPC5565 Microcontroller Reference Manual Devices Supported MPC5565 MPC5565 RM Rev 1 0 09 2007...
Page 34: ...MPC5565 Reference Manual Rev 1 0 Freescale Semiconductor 15...
Page 35: ...MPC5565 Reference Manual Rev 1 0 16 Freescale Semiconductor...
Page 553: ...Flash Memory MPC5565 Microcontroller Reference Manual Rev 1 0 13 38 Freescale Semiconductor...
Page 559: ...SRAM MPC5565 Microcontroller Reference Manual Rev 1 0 14 6 Freescale Semiconductor...
Page 973: ...Preface MPC5565 Microcontroller Reference Manual Rev 1 0 21 36 Freescale Semiconductor...
Page 1153: ...Calibration MPC5565 Microcontroller Reference Manual Rev 1 0 B 8 Freescale Semiconductor...