TMS320F243, TMS320F241
DSP CONTROLLERS
SPRS064B – DECEMBER 1997 – REVISED FEBRUARY 1999
92
POST OFFICE BOX 1443
HOUSTON, TEXAS 77251–1443
SPI slave mode external timing parameters (clock phase = 1)
(see Figure 37)
NO.
MIN
MAX
UNIT
12
tc(SPC)S
tw(SPCH)S
tw(SPCL)S
tw(SPCL)S
tw(SPCH)S
tsu(SOMI-SPCH)S
tsu(SOMI-SPCL)S
Cycle time, SPICLK
8tc(CO)
0.5tc(SPC)S–10
0.5tc(SPC)S–10
0.5tc(SPC)S–10
0.5tc(SPC)S–10
0.125tc(SPC)S
0.125tc(SPC)S
ns
13§
Pulse duration, SPICLK high (clock polarity = 0)
0.5tc(SPC)S
0.5tc(SPC)S
0.5tc(SPC)S
0.5tc(SPC)S
ns
Pulse duration, SPICLK low (clock polarity = 1)
14§
Pulse duration, SPICLK low (clock polarity = 0)
ns
Pulse duration, SPICLK high (clock polarity = 1)
17§
Setup time, SPISOMI before SPICLK high (clock polarity = 0)
ns
Setup time, SPISOMI before SPICLK low (clock polarity = 1)
18§
tv(SPCH-SOMI)S
Valid time, SPISOMI data valid after SPICLK high
(clock polarity =0)
0.75tc(SPC)S
ns
tv(SPCL-SOMI)S
Valid time, SPISOMI data valid after SPICLK low
(clock polarity =1)
0.75tc(SPC)S
21§
tsu(SIMO-SPCH)S
tsu(SIMO-SPCL)S
Setup time, SPISIMO before SPICLK high (clock polarity = 0)
0
ns
Setup time, SPISIMO before SPICLK low (clock polarity = 1)
0
22§
tv(SPCH-SIMO)S
Valid time, SPISIMO data valid after SPICLK high
(clock polarity = 0)
0.5tc(SPC)S
ns
tv(SPCL-SIMO)S
Valid time, SPISIMO data valid after SPICLK low
(clock polarity = 1)
0.5tc(SPC)S
The MASTER/SLAVE bit (SPICTL.2) is cleared and the CLOCK PHASE bit (SPICTL.3) is set.
tc = system clock cycle time = 1/CLKOUT = tc(CO)
§The active edge of the SPICLK signal referenced is controlled by the CLOCK POLARITY bit (SPICCR.6).