30-44
MC9328MX1 Reference Manual
MOTOROLA
Synchronous Serial Interface (SSI)
Figure 30-20. Rising Edge Clocking with Falling Edge Latching
Figure 30-21. Falling Edge Clocking with Rising Edge Latching
For gated clock operation in internal clock mode, only the rising edge transition to clock data (TSCKP=0)
and falling edge transition to latch data (RSCKP=0) is supported. The clock will always be in an active low
state when idle. TSCKP=1 and RSCKP=1 are not supported in internal clock mode.
NOTE:
The bit clock pins must be kept free of timing glitches. A single glitch
causes all subsequent transfers to lose synchronization.
When there is new data to be transmitted after the idle state has been entered, the data written to the
Transmit FIFO will be transmitted immediately.
30.7 External Frame and Clock Operation
When applying external frame sync and clock signals to SSI, at least 4 clock cycle delays should occur
before the rising edge of the frame sync signal. The transition of SSI_TXFS or SSI_RXFS is synchronized
with the rising edge of the external clock signal, SSI_TXCLK or SSI_RXCLK.
30.8 SSI Reset and Initialization Procedure
The SSI is affected by three types of reset:
•
Power-on reset—The power-on reset is generated by asserting either the RESET pin or the
Computer Operating Properly (COP) timer reset. The power-on reset clears the SSI_EN bit in the
SCSR and disables the SSI.
•
SSI reset—The SSI reset is generated when the SSI_EN bit in the SCSR is cleared. The SSI status
bits are reset to the same state produced by the power-on reset. The SSI control bits are unaffected.
The control bits in the top half of the SCSR are also unaffected. The SSI reset is useful for selective
reset of the SSI without changing the present SSI control bits and without affecting the other
peripherals.
STXD
SRXD
STCK
TSCKP=0, RSCKP=0
TSCKP=1, RSCKP=1
STXD
SRXD
STCK
Summary of Contents for DragonBall MC9328MX1
Page 68: ...1 12 MC9328MX1 Reference Manual MOTOROLA Introduction ...
Page 86: ...2 18 MC9328MX1 Reference Manual MOTOROLA Signal Descriptions and Pin Assignments ...
Page 116: ...3 30 MC9328MX1 Reference Manual MOTOROLA Memory Map ...
Page 126: ...4 10 MC9328MX1 Reference Manual MOTOROLA ARM920T Processor ...
Page 160: ...8 8 MC9328MX1 Reference Manual MOTOROLA System Control ...
Page 272: ...13 32 MC9328MX1 Reference Manual MOTOROLA DMA Controller ...
Page 281: ...Programming Model MOTOROLA Watchdog Timer Module 14 9 ...
Page 282: ...14 10 MC9328MX1 Reference Manual MOTOROLA Watchdog Timer Module ...
Page 300: ...15 18 MC9328MX1 Reference Manual MOTOROLA Analog Signal Processor ASP ...
Page 438: ...18 16 MC9328MX1 Reference Manual MOTOROLA Serial Peripheral Interface Modules SPI 1 and SPI 2 ...
Page 478: ...19 40 MC9328MX1 Reference Manual MOTOROLA LCD Controller ...
Page 574: ...21 32 MC9328MX1 Reference Manual MOTOROLA Memory Stick Host Controller MSHC Module ...
Page 598: ...23 16 MC9328MX1 Reference Manual MOTOROLA Real Time Clock RTC ...
Page 670: ...24 72 MC9328MX1 Reference Manual MOTOROLA SDRAM Memory Controller ...
Page 726: ...25 56 MC9328MX1 Reference Manual MOTOROLA SmartCard Interface Module SIM ...
Page 736: ...26 10 MC9328MX1 Reference Manual MOTOROLA General Purpose Timers ...
Page 854: ...29 18 MC9328MX1 Reference Manual MOTOROLA I2C Module ...
Page 900: ...30 46 MC9328MX1 Reference Manual MOTOROLA Synchronous Serial Interface SSI ...
Page 942: ...32 26 MC9328MX1 Reference Manual MOTOROLA GPIO Module and I O Multiplexer IOMUX ...