Clock
(
)
EPI0S31
Frame
(
)
EPI0S30
RD
(
)
EPI0S29
WR
(
)
EPI0S28
Clock
(
)
EPI0S31
Frame
(
)
EPI0S30
RD
(
)
EPI0S29
WR
(
)
EPI0S28
Clock
(
)
EPI0S31
Frame
(
)
EPI0S30
RD
(
)
EPI0S29
WR
(
)
EPI0S28
General-Purpose Mode
1257
SPRUHE8E – October 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
External Peripheral Interface (EPI)
17.8.1.1 FRAME Signal Operation
The operation of the FRAME signal is controlled by the FRMCNT and FRM50 bits. When FRM50 is clear,
the FRAME signal is high whenever the WR or RD strobe is high. When FRMCNT is clear, the FRAME
signal is simply the logical OR of the WR and RD strobes, so the FRAME signal is high during every read
or write access. See
Figure 17-18. FRAME Signal Operation, FRM50 = 0 and FRMCNT = 0
If the FRMCNT field is 0x1, then the FRAME signal pulses high during every other read or write access.
See
Figure 17-19. FRAME Signal Operation, FRM50 = 0 and FRMCNT = 1
If the FRMCNT field is 0x2 and FRM50 is clear, then the FRAME signal pulses high during every third
access, and so on for every value of FRMCNT. See
.
Figure 17-20. FRAME Signal Operation, FRM50 = 0 and FRMCNT = 2
When FRM50 is set, the FRAME signal transitions on the rising edge of either the WR or RD strobes.
When FRMCNT=0, the FRAME signal transitions on the rising edge of WR or RD for every access. See
.