![Freescale Semiconductor MPC5632M Скачать руководство пользователя страница 1033](http://html.mh-extra.com/html/freescale-semiconductor/mpc5632m/mpc5632m_manual_23306591033.webp)
MPC563XM Reference Manual, Rev. 1
Freescale Semiconductor
1033
Preliminary—Subject to Change Without Notice
describes the important components in the CFIFO. Each CFIFO is implemented as a circular
set of registers to avoid the need to move all entries at each push/pop operation. The Push Next Data
Pointer points to the next available CFIFO location for storing data written into the EQADC Command
FIFO Push Register. The Transfer Next Data Pointer points to the next entry to be removed from CFIFOx
when it completes a transfer. The
CFIFO Transfer Counter Control Logic
counts the number of entries in
the CFIFO and generates DMA or interrupt requests to fill the CFIFO. TNXTPTR in
“EQADC FIFO and Interrupt Status Registers (EQADC_FISR)
indicates the index of the entry that is
currently being addressed by the Transfer Next Data Pointer, and CFCTR, in the same register, provides
the number of entries stored in the CFIFO. Using TNXTPTR and CFCTR, the absolute addresses for the
entries indicated by the Transfer Next Data Pointer and by the Push Next Data Pointer can be calculated
using the following formulas:
Transfer Next Data Pointer Address = CFIFOx_BASE_A TNXTPTRx*4
Push Next Data Pointer Address = CFIFOx_BASE_A
[(TCFCTRx) mod CFIFO_DEPTH] * 4
where
•
a
mod b
returns the remainder of the division of
a
by
b
.
•
CFIFOx_BASE_ADDRESS is the smallest memory mapped address allocated to a CFIFOx entry.
•
CFIFO_DEPTH is the number of entries contained in a CFIFO - four in this implementation.
When CFS
x
Section 24.5.2.12, “EQADC CFIFO Status Register (EQADC_CFSR)
is TRIGGERED,
the EQADC generates the proper control signals for the transfer of the entry pointed by Transfer Next Data
Pointer. CFUFx
Section 24.5.2.9, “EQADC FIFO and Interrupt Status Registers (EQADC_FISR)
when a CFIFOx underflow event occurs. A CFIFO underflow occurs when the CFIFO is in TRIGGERED
state and it becomes empty. No commands will be transferred from an underflowing CFIFO, nor will
command transfers from lower priority CFIFOs be blocked. CFIFOx is empty when the Transfer Next
Data Pointer x equals the Push Next Data Pointer x and CFCTRx is zero. CFIFOx is full when the Transfer
Next Data Pointer x equals the Push Next Data Pointer x and CFCTRx is not zero.
When the EQADC completes the transfer of an entry from CFIFOx: the transferred entry is popped from
CFIFOx, the CFIFO counter CFCTR in the
Section 24.5.2.9, “EQADC FIFO and Interrupt Status
is decremented by one, and Transfer Next Data Pointer x is incremented by one
(or wrapped around) to point to the next entry in the CFIFO. The transfer of entries bound for the on-chip
ADCs is considered completed when they are stored in the appropriate CBuffer. The transfer of entries
bound for the external device is considered completed when the serial transmission of the entry is
completed.
When the EQADC_CFPRx is written and CFIFOx is not full, the CFIFO counter CFCTRx is incremented
by one, and the Push Next Data Pointer x then is incremented by one (or wrapped around) to point to the
next entry in the CFIFO.
When the EQADC_CFPRx is written but CFIFOx is full, the EQADC will not increment the counter value
and will not overwrite any entry in CFIFOx.
Содержание MPC5632M
Страница 22: ...MPC563XM Reference Manual Rev 1 22 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 62: ...MPC563XM Reference Manual Rev 1 62 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 92: ...MPC563XM Reference Manual Rev 1 92 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 168: ...MPC563XM Reference Manual Rev 1 168 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 242: ...MPC563XM Reference Manual Rev 1 242 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 302: ...MPC563XM Reference Manual Rev 1 302 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 410: ...MPC563XM Reference Manual Rev 1 410 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 440: ...MPC563XM Reference Manual Rev 1 440 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 464: ...MPC563XM Reference Manual Rev 1 464 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 554: ...MPC563XM Reference Manual Rev 1 554 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 590: ...MPC563XM Reference Manual Rev 1 590 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 622: ...MPC563XM Reference Manual Rev 1 622 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 716: ...MPC563XM Reference Manual Rev 1 716 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 1114: ...MPC563XM Reference Manual Rev 1 1114 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 1144: ...MPC563XM Reference Manual Rev 1 1144 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 1266: ...MPC563XM Reference Manual Rev 1 1266 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 1316: ...MPC563XM Reference Manual Rev 1 1316 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 1348: ...MPC563XM Reference Manual Rev 1 1348 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 1362: ...MPC563XM Reference Manual Rev 1 1362 Freescale Semiconductor Preliminary Subject to Change Without Notice ...
Страница 1382: ...MPC563XM Reference Manual Rev 1 1382 Freescale Semiconductor Preliminary Subject to Change Without Notice ...