Table 49-7. SPI Master (CPHA=1) Configuration (continued)
Register
Value
Comments
Set TIMCMP[7:0] = (baud rate divider /
2) - 1.
TIMCFGn
0x0100_2222
Configure start bit, stop bit, enable on
trigger high and disable on compare,
initial clock state is logic 0. Set PINPOL
to invert the output shift clock. Set
TIMDIS=3 to keep slave select asserted
for as long as there is data in the
transmit buffer.
TIMCTLn
0x01C3_0201
Configure dual 8-bit counter using Pin 2
output (shift clock), with Shifter 0 flag as
the inverted trigger.
TIMCMP(n+1)
0x0000_FFFF
Never compare.
TIMCFG(n+1)
0x0000_1100
Enable when Timer 0 is enabled and
disable when Timer 0 is disabled.
TIMCTL(n+1)
0x0003_0383
Configure 16-bit counter (never
compare) using inverted Pin 3 output (as
slave select).
SHIFTBUFn
Data to transmit
Transmit data can be written to
SHIFTBUF, use the Shifter Status Flag
to indicate when data can be written
using interrupt or DMA request. Can
support MSB first transfer by writing to
SHIFTBUFBBS register instead.
SHIFTBUF(n+1)
Data to receive
Received data can be read from
SHIFTBUFBYS, use the Shifter Status
Flag to indicate when data can be read
using interrupt or DMA request. Can
support MSB first transfer by reading
from SHIFTBUFBIS register instead.
49.5.4 SPI Slave
SPI slave mode can be supported using one Timer, two Shifters and four Pins. Either
CPHA=0 or CPHA=1 can be supported and transfers can be supported using the DMA
controller. For CPHA=1, the select can remain asserted for multiple transfers and the
timer status flag can be used to indicate the end of the transfer.
The transmit data must be written to the transmit buffer register before the external slave
select asserts, otherwise the shifter error flag will be set.
Due to synchronization delays, the output valid time for the serial output data is 2.5
FlexIO clock cycles, so the maximum baud rate is divide by 6 of the FlexIO clock
frequency.
Chapter 49 Flexible I/O (FlexIO)
Kinetis KE1xF Sub-Family Reference Manual, Rev. 4, 06/2019
NXP Semiconductors
1367
Содержание KE1xF Series
Страница 2: ...Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 2 NXP Semiconductors...
Страница 60: ...SysTick Clock Configuration Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 60 NXP Semiconductors...
Страница 114: ...Initialization application information Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 114 NXP Semiconductors...
Страница 138: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 138 NXP Semiconductors...
Страница 320: ...Private Peripheral Bus PPB memory map Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 320 NXP Semiconductors...
Страница 342: ...Functional Description Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 342 NXP Semiconductors...
Страница 360: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 360 NXP Semiconductors...
Страница 490: ...Interrupts Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 490 NXP Semiconductors...
Страница 550: ...Memory map and register definition Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 550 NXP Semiconductors...
Страница 562: ...Boot Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 562 NXP Semiconductors...
Страница 662: ...Power supply supervisor Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 662 NXP Semiconductors...
Страница 694: ...On chip resource access control mechanism Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 694 NXP Semiconductors...
Страница 706: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 706 NXP Semiconductors...
Страница 724: ...Application Information Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 724 NXP Semiconductors...
Страница 736: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 736 NXP Semiconductors...
Страница 750: ...Debug and Security Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 750 NXP Semiconductors...
Страница 798: ...Functional description Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 798 NXP Semiconductors...
Страница 808: ...Functional description Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 808 NXP Semiconductors...
Страница 866: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 866 NXP Semiconductors...
Страница 1164: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1164 NXP Semiconductors...
Страница 1178: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1178 NXP Semiconductors...
Страница 1380: ...Usage Guide Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1380 NXP Semiconductors...
Страница 1472: ...Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1472 NXP Semiconductors...
Страница 1482: ...Kinetis KE1xF Sub Family Reference Manual Rev 4 06 2019 1482 NXP Semiconductors...