TMS320C6727, TMS320C6726, TMS320C6722

Floating-Point Digital Signal Processors

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SPRS268E –MAY 2005 –REVISED JANUARY 2007

Figure 4-17illustrates the Non-Multiplexed Host Address/Data Fullword mode of the UHPI. In this mode, the UHPI behaves almost like an asynchronous SRAM except it asserts the UHPI_HRDY signal. This mode allows the host to randomly access a 64K-byte page in the C672x address space. The upper 32 bits of the C672x address are set by the DSP (only) through the CFGHPIAMSB and CFGHPIAUMB registers (see Table 4-13and Table 4-14).

DSP

EM_D[31:16]/UHPI_HA[15:0]

UHPI_HCNTL[1:0]

UHPI_HD[15:0]

UHPI_HD[16]/HHWIL

UHPI_HD[31:17]

UHPI_HAS(B)

UHPI_HBE[3:0]

UHPI_HRW

UHPI_HDS[2]

UHPI_HDS[1]

UHPI_HCS

UHPI_HRDY

AMUTE2/HINT

External Host MCU

A[17:2]

A[x:y](A)

D[15:0]

D[16]

D[31:17]

BE[3:0](C)

R/W

WE(D)

RD(D)

CS

RDY

INTERRUPT

A.Two host address lines or host GPIO if address lines are not available.

B.Not used in this mode.

C.Byte Enables (active during reads and writes). Some processors support a byte-enable mode on their write enable pins.

D.Only required if needed for strobe timing. Not required if CS meets strobe timing requirements.

Figure 4-17. UHPI Non-Multiplexed Host Address/Data Fullword Mode

CAUTION

The EMIF data bus and UHPI HA inputs share the EM_D[31:16]/UHPI_HA[15:0] pins. When using Non-Multiplexed mode, make sure the EMIF does not drive EM_D[31:16]; otherwise, a drive conflict with the external host MCU may result. Normally, the EMIF will begin to drive the EM_D[31:16] lines immediately after it completes the SDRAM initialization sequence, which occurs automatically after RESET is released. To avoid a drive conflict then, the boot software must set CFGHPI.NMUX to '1'before the EMIF drives EM_D[31:16]. Setting CFGHPI.NMUX to '1'forces these pins to be input pins.

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Peripheral and Electrical Specifications

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Texas Instruments TMS320C6722, TMS320C6727, TMS320C6726 warranty Uhpi Non-Multiplexed Host Address/Data Fullword Mode