Texas Instruments Digital Signal Processor SM320F2812-HT User Manual

Page 145

Advertising
background image

Bit 0

Bit(n-1)

(n-2)

(n-3)

(n-4)

Bit 0

Bit(n-1)

(n-2)

(n-3)

(n-4)

CLKX

FSX

DX

DR

M54

M58

M56

M53

M55

M59

M57

LSB

MSB

M60

M61

SM320F2812-HT

www.ti.com

SGUS062B

JUNE 2009

REVISED JUNE 2011

Table 6-60. McBSP as SPI Master or Slave Timing Requirements (CLKSTP = 11b, CLKXP = 1)

(1)

MASTER

SLAVE

NO.

UNIT

MIN

MAX

MIN

MAX

M58

t

su(DRV-CKXL)

Setup time, DR valid before CLKX low

P

10

8P

10

ns

M59

t

h(CKXL-DRV)

Hold time, DR valid after CLKX low

P

10

8P

10

ns

M60

t

su(FXL-CKXL)

Setup time, FSX low before CLKX low

16P + 10

ns

M61

t

c(CKX)

Cycle time, CLKX

2P

16P

ns

(1)

Not production tested.

Table 6-61. McBSP as SPI Master or Slave Switching Characteristics (CLKSTP = 11b, CLKXP = 1)

(1) (2)

MASTER

(3)

SLAVE

NO.

PARAMETER

UNIT

MIN

MAX

MIN

MAX

M53

t

h(CKXH-FXL)

Hold time, FSX low after CLKX high

P

ns

M54

t

d(FXL-CKXL)

Delay time, FSX low to CLKX low

2P

ns

Disable time, DX high impedance following last data bit from CLKX

M56

t

dis(CKXH-DXHZ)

P + 6

7P + 6

ns

high

M57

t

d(FXL-DXV)

Delay time, FSX low to DX valid

6

4P + 6

ns

(1)

Not production tested.

(2)

2P = 1/CLKG
For all SPI slave modes, CLKX has to be minimum eight CLKG cycles. Also, CLKG should be LSPCLK/2 by setting CLKSM = CLKGDV
= 1. With maximum LSPCLK speed of 75 MHz, CLKX maximum frequency is LSPCLK/16, that is 4.5 MHz and P = 13.3 ns.

(3)

C = CLKX low pulse width = P
D = CLKX high pulse width = P

Figure 6-46. McBSP Timing as SPI Master or Slave: CLKSTP = 11b, CLKXP = 1

Copyright

©

2009

2011, Texas Instruments Incorporated

Electrical Specifications

145

Submit Documentation Feedback

Product Folder Link(s):

SM320F2812-HT

Advertising