JTAG IN-SYSTEM PROGRAMMING
Programming devices in-system provides a number of significant benefits including: rapid
prototyping, lower inventory levels, higher quality, and the ability to make in-field modifications.
All MACHxxxSP devices provide in-system programming (ISP) capability through their JTAG ports.
This capability has been implemented in a manner that insures that the JTAG port remains
compliant to the IEEE 1149.1 standard. By using JTAG as the communication interface through
which ISP is achieved, customers benefit from a standard, well-defined interface.
MACHxxxSP devices can be programmed across the commercial temperature and voltage range.
These devices tristate the outputs during programming. Lattice/Vantis provides its free PC-based
Lattice/VantisPRO software to facilitate in-system programming. Lattice/VantisPRO software takes
the JEDEC file output produced by Vantis’ design implementation software, along with information
about the JTAG chain, and creates a set of vectors that are used to drive the JTAG chain. Lattice/
VantisPRO software can use these vectors to drive a JTAG chain via the parallel port of a PC.
Alternatively, Lattice/VantisPRO software can output files in formats understood by common
automated test equipment. This equipment can then be used to program MACHxxxSP devices
during the testing of a circuit board. For more information about in-system programming, refer to
the separate document entitled MACH ISP Manual.
BUS-FRIENDLY INPUTS AND I/Os
The MACH 1 & 2 inputs and I/Os include two inverters in series which loop back to the input.
This double inversion weakly holds the input at its last driven logic state. For the circuit diagram,
please refer to the Input/Output Equivalent Schematics (page 393) in the General Information
Section of the Vantis 1999 Data Book.
PCI COMPLIANT
The MACH 1 & 2 families in -5/-6/-7/-10/-12 speed grades are fully compliant with the PCI Local
Bus Specification published by the PCI Special Interest Group. The MACH 1 & 2 families’
predictable timing ensures compliance with the PCI AC specifications independent of the design.
POWER-DOWN MODE
The MACH 1 & 2 families feature a programmable low-power mode in which individual signal
paths can be programmed for low power. These low-power speed paths will be slower than the
non-low-power paths. This feature allows speed critical paths to run at maximum frequency while
the rest of the paths operate in the low-power mode, resulting in power savings of up to 75%. If
all of the signals in a PAL block are in low-power mode, then the total power is reduced even
further.
SAFE FOR MIXED SUPPLY VOLTAGE SYSTEM DESIGNS
All MACHxxxSP and most of the MACH 1 & 2 devices are safe for mixed supply voltage system
designs. These 5-V devices will not overdrive 3.3-V devices above the output voltage of 3.3 V,
while they can accept inputs from other 3.3-V devices. The MACH 1 & 2 families provide easy-to-
use mixed-voltage design compatibility. For more information, refer to the Technical Note entitled
Mixed Supply Design with MACH 1 & 2 SP Devices.
POWER-UP RESET
All flip-flops power-up to a logic LOW for predictable system initialization. The actual values of
the outputs of the MACH devices will depend on the configuration of the macrocell. To guarantee
MACH 1 & 2 Families
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LATTICE [ LATTICE SEMICONDUCTOR ]
