m5lv-128-104-10yi Lattice Semiconductor Corp., m5lv-128-104-10yi Datasheet - Page 6

• Manufacturer Part Number: m5lv-128-104-10yi
• Description: Mach 5 Cpld Family Fifth Generation Mach Architecture
• Manufacturer: Lattice Semiconductor Corp.

Macrocells
The macrocells for MACH 5 devices consist of a storage element which can be configured for
combinatorial, registered or latched operation (Figure 3). The D-type flip-flops can be configured
as T-type, J-K, or S-R operation through the use of the XOR gate associated with each macrocell.
Each PAL block has the capability to provide two input registers by using macrocells 0 and 15. In
order to use this option, these macrocells must be accessed via the I/O pins associated with
macrocells 3 and 12, respectively. Once the macrocell is used as an input register, it cannot be used
for logic, so its clusters can be re-directed through the logic allocator to another macrocell. The
I/O pins associated with macrocells 0 and 15 can still be used as input pins. Although the I/O pins
for macrocells 3 and 12 are used to connect to the input registers, these macrocells can still be
used as “buried” macrocells to drive device logic via the matrix.
Control Generator
The control generator provides four configurable clock lines and three configurable set/reset lines to
each macrocell in a PAL block. Any of the four clock lines and any of the three set/reset lines can
be independently selected by any flip-flop within a block. The clock lines can be configured to
provide synchronous global (pin) clocks and asynchronous product term clocks, sum term clocks,
and latch enables (Figure 4). Three of the four global clocks, as well as two product-term clocks
and one sum-term clock, are available per PAL block. Positive or negative edge clocking is
available as well as advanced clocking features such as complementary and biphase clocking.
Complementary clocking provides two clock lines exactly 180 degrees out of phase, and is useful
in applications such as fast data paths. A biphase clock line clocks flip-flops on both the positive
and negative edges of the clock. The configuration options for the four clock lines per PAL block
are as follows:
Clock Line 0 Options
6
Global clock (0, 1, 2, or 3) with positive or negative edge clock enable
Product-term clock (A*B*C)
Sum-term clock (A+B+C)
Allocator
Clusters/
Logic
MC
5-8
Figure 3. Macrocell Diagram
Prog. Polarity
MACH 5 Family
D
Selection
Mode
Macrocell
Q
20446G-003