
TM1300 Data Book
Philips Semiconductors
17-12
PRODUCT SPECIFICATION
17.11 TIMING DIAGRAMS
Figure 17-11
and
Figure 17-12
illustrate the timing of the
data signals and the frame timing.
17.12 POWER DOWN
SSI block can be separately powered down by setting a
bit in the BLOCK_POWER_DOWN register. For a de-
scription of powerdown, see
Chapter 21, “Power Man-
agement.”
The SSI block should not be active when ap-
plying block powerdown.
If the block enters power-down state while transmission
is enabled, behavior upon power-up is undefined.
Table 17-9. Test mode select
Bit
Mode
0X
10
Normal Operation.
Remote Loopback Test:
Direct connection of receiver serial data to transmitter serial data. Transmitter is
clocked with RxCLK. No data loaded to the SSI_RxDR register or RxFIFO buffer and no CPU interrupt is gener-
ated. Useful to allow remote device to test the communication medium and the Rx and Tx front ends.
Local Loopback Test:
Feedback is after SSI_TxDR and SSI_RxDR register and serializer/deserializer. Allows
DSPCPU to test the bulk of the Rx and Tx circuits. During Local Loopback Test, an external clock on
SSI_RXCLK should be present to clock the SSI unit.
11
Figure 17-11. SSI Serial timing. (FSP = 0, RSD = 0, TSD = 0, TCP = 0, RCP = 0, FMS = 0)
SSI_RXCLK
SSI_RXFSX
SSI_RXDATA
SSI_TXDATA
D0
D15
D14
D13
D12
D0
D15
D14
D13
D12
D11
D10
D9
D8
D11
D10
D9
D8
D7
D6
D5
D4
D7
D6
D5
D4
D3
D2
D1
D0
D3
D2
D1
D0
D15
D14
D13
D12
D15
D14
D13
D12
Figure 17-12. SSI Serial timing. (FSP = 0, RSD = 0, TSD = 0, TCP = 0, RCP = 0, FMS = 0, FSS = 5, VSS = 4)
SSI_RXCLK
SSI_RXFSX
SSI_RXDATA
SSI_TXDATA
1st DATA
1st DATA
1st Frame
2nd DATA
2nd DATA
3th DATA
3th DATA
4th DATA
4th DATA
1st DATA
1st DATA
2nd Frame