10
10
01
01
01
1st halfword
2nd halfword
1st halfword
2nd halfword
1st halfword
Interna
l
HSTRB
UHPI_HD[15:0]
UHPI_HRDY
UHPI_HHWIL
UHPI_HR/W
UHPI_HCNTL[1:0]
UHPI_HAS
UHPI_HCS
10
10
11
11
1st halfword
2nd halfword
2nd halfword
1st halfword
Internal
HSTRB
UHPI_HD[15:0]
UHPI_HRDY
UHPI_HHWIL
UHPI_HR/W
UHPI_HCNTL[1:0]
UHPI_HAS
UHPI_HCS
1st halfword
2nd halfword
00
00
Internal
UHPI_HD[15:0]
UHPI_HRDY
UHPI_HHWIL
UHPI_HR/W
UHPI_HCNTL[1:0]
UHPI_HAS
UHPI_HCS
HSTRB
Architecture
969
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Host Port Interface (HPI)
21.2.6.9.2
UHPI_HRDY Behavior During Multiplexed-Mode Write Operations
shows an HPIC (UHPI_HCNTL[1:0] = 00b) write cycle operation. An HPIC write cycle does
not cause UHPI_HRDY to go high and the state of UHPI_HHWIL is ignored. Firmware is not required to
perform a dual access to access HPIC.
Figure 21-10. UHPI_HRDY Behavior During an HPIC Write Cycle in the Multiplexed Mode
includes a HPID write cycle without autoincrementing. The host writes the memory address
while UHPI_HCNTL[1:0] = 10b and writes the data while UHPI_HCNTL[1:0] = 11b. During the HPID write
cycle, UHPI_HRDY goes high only for the second halfword access.
Figure 21-11. UHPI_HRDY Behavior During a Data Write Operation in the Multiplexed Mode
(Case 1: No Autoincrementing)
shows autoincrement HPID write cycles when the write FIFO is empty prior to the HPIA
write. The host writes the memory address while UHPI_HCNTL[1:0] = 10b and writes the data while
UHPI_HCNTL[1:0] = 01b. UHPI_HRDY does not go high during any of the HPID write cycles until the
FIFO is full.
Figure 21-12. UHPI_HRDY Behavior During a Data Write Operation in the Multiplexed Mode
(Case 2: Autoincrementing Selected, FIFO Empty Before Write)