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Terminal Functions
78
July 2002 Revised March 2004
SPRS200E
Table 210. Terminal Functions (Continued)
SIGNAL
TYPE
IPD/
IPU
DESCRIPTION
NAME
NO.
TYPE
IPD/
IPU
DESCRIPTION
RESETS, INTERRUPTS, AND GENERAL-PURPOSE INPUT/OUTPUTS (CONTINUED)
GP0[7]/EXT_INT7
E1
I/O/Z
IPU
General-purpose input/output (GPIO) pins (I/O/Z) or external interrupts (input only).
The default after reset setting is GPIO enabled as input-only.
GP0[6]/EXT_INT6
F2
I/O/Z
IPU
General-purpose input/output (GPIO) pins (I/O/Z) or external interrupts (input only).
The default after reset setting is GPIO enabled as input-only.
When these pins function as External Interrupts [by selecting the corresponding
GP0[5]/EXT_INT5
F3
I/O/Z
IPU
When these pins function as External Interrupts [by selecting the corresponding
interrupt enable register bit (IER.[7:4])], they are edge-driven and the polarity can be
independently selected via the External Interrupt Polarity Register bits
GP0[4]/EXT_INT4
F4
I/O/Z
IPU
independently selected via the External Interrupt Polarity Register bits
(EXTPOL.[3:0]).
GP0[15]/PRST§
G3
General-purpose input/output (GP0) 15 pin (I/O/Z) or PCI reset (I). No function at
default.
GP0[14]/PCLK§
C1
GP0 14 pin (I/O/Z) or PCI clock (I). No function at default.
GP0[13]/PINTA§
G4
GP0 13 pin (I/O/Z) or PCI interrupt A (O/Z). No function at default.
GP0[12]/PGNT§
H4
GP0 12 pin (I/O/Z) or PCI bus grant (I). No function at default.
GP0[11]/PREQ§
F1
I/O/Z
GP0 11 pin (I/O/Z) or PCI bus request (O/Z). No function at default.
GP0[10]/PCBE3§
J2
I/O/Z
GP0 10 pin (I/O/Z) or PCI command/byte enable 3 (I/O/Z). No function at default.
GP0[9]/PIDSEL§
K3
GP0 9 pin (I/O/Z) or PCI initialization device select (I). No function at default.
GP0[3]/PCIEEAI
L5
IPD
GP0 3 pin (I/O/Z) and PCI EEPROM Auto-Initialization (EEAI).
If the PCI peripheral is disabled (PCI_EN pin = 0), this pin must not be pulled up.
0
PCI auto-initialization through EEPROM is disabled (default).
1
PCI auto-initialization through EEPROM is enabled.
GP0[0]
M5
I/O/Z
IPD
GP0 0 pin (I/O/Z) [default] or device selection (I) [default]
The general-purpose 0 pin (GP0[0]) (I/O/Z) can be programmed as GPIO 0 (input
only) [default] or as GP0[0] (output only) pin or output as a general-purpose interrupt
(GP0INT) signal (output only). This pin must remain low during device reset.
VDAC/
GP0[8]/PCI66§
AD1
I/O/Z
IPD
VCXO Interpolated Control Port (VIC) single-bit digital-to-analog converter (VDAC)
output [output only] [default] or this pin can be programmed as a GP0 8 pin (I/O/Z) or
PCI frequency selection (PCI66).
If the PCI peripheral is enabled (PCI_EN pin = 1), then:
0
PCI operates at 66 MHz (default).
1
PCI operates at 33 MHz.
The -500 device supports PCI at 33 MHz only. For proper -500 device operation when
the PCI peripheral is enabled (PCI_EN = 1), this pin must be pulled up with a a 1-k
resistor at device reset.
If the PCI peripheral is disabled (PCI_EN pin = 0), this pin must not be pulled up.
CLKOUT6/
GP0[2]§
C6
I/O/Z
IPD
Clock output at 1/6 of the device speed (O/Z) [default] or this pin can be programmed as
a GP0 2 pin (I/O/Z).
CLKOUT4/
GP0[1]§
D6
I/O/Z
IPD
Clock output at 1/4 of the device speed (O/Z) [default] or this pin can be programmed as
a GP0 1 pin (I/O/Z).
HOST-PORT INTERFACE (HPI) OR PERIPHERAL COMPONENT INTERCONNECT (PCI) OR EMAC
PCI_EN
E2
I
IPD
PCI enable pin. This pin and the MAC_EN pin control the selection (enable/disable) of
the HPI, EMAC, MDIO, and GP0[15:8], or PCI peripherals. The pins work in conjunction
to enable/disable these peripherals (for more details, see the Device Configurations
section of this data sheet).
HINT/PFRAME§
N4
I/O/Z
Host interrupt from DSP to host (O) [default] or PCI frame (I/O/Z)
I = Input, O = Output, Z = High impedance, S = Supply voltage, GND = Ground
IPD = Internal pulldown, IPU = Internal pullup. (These IPD/IPU signal pins feature a 30-k IPD or IPU resistor. To pull up a signal to the opposite
supply rail, a 1-k
resistor should be used.)
§ These pins are multiplexed pins. For more details, see the Device Configurations section of this data sheet.
ADV
ANCE
INFORMA
TION