Datasheet

TMS320F28069, TMS320F28068, TMS320F28067, TMS320F28066
TMS320F28065, TMS320F28064, TMS320F28063, TMS320F28062
SPRS698D –NOVEMBER 2010–REVISED DECEMBER 2012 www.ti.com
Table 2-5. Terminal Functions
(1)
(continued)
PIN NO.
PIN NAME I/O/Z DESCRIPTION
PZ PN
PZP PFP
CLOCK
See GPIO18. Output clock derived from SYSCLKOUT. XCLKOUT is either the same
frequency, one-half the frequency, or one-fourth the frequency of SYSCLKOUT. This is
controlled by bits 1:0 (XCLKOUTDIV) in the XCLK register. At reset, XCLKOUT =
XCLKOUT See GPIO18 O/Z
SYSCLKOUT/4. The XCLKOUT signal can be turned off by setting XCLKOUTDIV to 3.
The mux control for GPIO18 must also be set to XCLKOUT for this signal to propogate
to the pin.
See GPIO19 and GPIO38. External oscillator input. Pin source for the clock is
controlled by the XCLKINSEL bit in the XCLK register, GPIO38 is the default selection.
This pin feeds a clock from an external 3.3-V oscillator. In this case, the X1 pin, if
available, must be tied to GND and the on-chip crystal oscillator must be disabled via
bit 14 in the CLKCTL register. If a crystal or resonator is used, the XCLKIN path must
See GPIO19 and
XCLKIN I be disabled by bit 13 in the CLKCTL register.
GPIO38
NOTE: Designs that use the GPIO38/XCLKIN/TCK pin to supply an external clock for
normal device operation may need to incorporate some hooks to disable this path
during debug using the JTAG connector. This is to prevent contention with the TCK
signal, which is active during JTAG debug sessions. The zero-pin internal oscillators
may be used during this time to clock the device.
On-chip crystal-oscillator input. To use this oscillator, a quartz crystal or a ceramic
resonator must be connected across X1 and X2. In this case, the XCLKIN path must
X1 60 48 I
be disabled by bit 13 in the CLKCTL register. If this pin is not used, it must be tied to
GND.
On-chip crystal-oscillator output. A quartz crystal or a ceramic resonator must be
X2 59 47 O
connected across X1 and X2. If X2 is not used, it must be left unconnected.
RESET
Device Reset (in) and Watchdog Reset (out). Piccolo devices have a built-in power-on-
reset (POR) and brown-out-reset (BOR) circuitry. As such, no external circuitry is
needed to generate a reset pulse. During a power-on or brown-out condition, this pin is
driven low by the device. See Section 4.3, Electrical Characteristics, for thresholds of
the POR/BOR block. This pin is also driven low by the MCU when a watchdog reset
occurs. During watchdog reset, the XRS pin is driven low for the watchdog reset
duration of 512 OSCCLK cycles. If need be, an external circuitry may also drive this pin
XRS 11 9 I/O
to assert a device reset. In this case, it is recommended that this pin be driven by an
open-drain device. An R-C circuit must be connected to this pin for noise immunity
reasons. Regardless of the source, a device reset causes the device to terminate
execution. The program counter points to the address contained at the location
0x3FFFC0. When reset is deactivated, execution begins at the location designated by
the program counter. The output buffer of this pin is an open-drain with an internal
pullup.
ADC, COMPARATOR, ANALOG I/O
ADCINA7 16 – I ADC Group A, Channel 7 input
ADCINA6 17 14 I ADC Group A, Channel 6 input
COMP3A I Comparator Input 3A
AIO6 I/O Digital AIO 6
ADCINA5 18 15 I ADC Group A, Channel 5 input
ADCINA4 19 16 I ADC Group A, Channel 4 input
COMP2A I Comparator Input 2A
AIO4 I/O Digital AIO 4
ADCINA3 20 – I ADC Group A, Channel 3 input
ADCINA2 21 17 I ADC Group A, Channel 2 input
COMP1A I Comparator Input 1A
AIO2 I/O Digital AIO 2
ADCINA1 22 18 I ADC Group A, Channel 1 input
ADC Group A, Channel 0 input.
ADCINA0 23 19 I NOTE: V
REFHI
and ADCINA0 share the same pin on the 80-pin PN and PFP devices
and their use is mutually exclusive to one another.
22 Device Overview Copyright © 2010–2012, Texas Instruments Incorporated
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TMS320F28064 TMS320F28063 TMS320F28062