uPSD3234A, uPSD3234BV, uPSD3233B, uPSD3233BV
Output Macrocell (OMC)
Eight of the Output Macrocells (OMC) are con-
nected to Ports A and B pins and are named as
McellAB0-McellAB7. The other eight macrocells
are connected to Ports B and C pins and are
named as McellBC0-McellBC7. If an McellAB out-
put is not assigned to a specific pin in PSDsoft, the
Macrocell Allocator block assigns it to either Port A
or B. The same is true for a McellBC output on Port
B or C. Table
shows the macrocells and port
assignment.
The Output Macrocell (OMC) architecture is
shown in
As shown in the
figure, there are native product terms available
from the AND Array, and borrowed product terms
available (if unused) from other Output Macrocells
(OMC). The polarity of the product term is con-
trolled by the XOR gate. The Output Macrocell
(OMC) can implement either sequential logic, us-
ing the flip-flop element, or combinatorial logic.
The multiplexer selects between the sequential or
combinatorial logic outputs. The multiplexer output
can drive a port pin and has a feedback path to the
AND Array inputs.
The flip-flop in the Output Macrocell (OMC) block
can be configured as a D, T, JK, or SR type in PS-
Dsoft. The flip-flop’s clock, preset, and clear inputs
may be driven from a product term of the AND Ar-
ray. Alternatively, CLKIN (PD1) can be used for
the clock input to the flip-flop. The flip-flop is
clocked on the rising edge of CLKIN (PD1). The
preset and clear are active High inputs. Each clear
input can use up to two product terms.
Table 91. Output Macrocell Port and Data Bit Assignments
Output
Macrocell
McellAB0
McellAB1
McellAB2
McellAB3
McellAB4
McellAB5
McellAB6
McellAB7
McellBC0
McellBC1
McellBC2
McellBC3
McellBC4
McellBC5
McellBC6
McellBC7
Port
Assignment
(1,2)
Port A0, B0
Port A1, B1
Port A2, B2
Port A3, B3
Port A4, B4
Port A5, B5
Port A6, B6
Port A7, B7
Port B0
Port B1
Port B2, C2
Port B3, C3
Port B4, C4
Port B5
Port B6
Port B7, C7
Native Product Terms
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
Maximum Borrowed
Product Terms
6
6
6
6
6
6
6
6
5
5
5
5
6
6
6
6
Data Bit for Loading or
Reading
D0
D1
D2
D3
D4
D5
D6
D7
D0
D1
D2
D3
D4
D5
D6
D7
Note: 1. McellAB0-McellAB7 can only be assigned to Port B in the 52-pin package.
2. Port PC0, PC1, PC5, and PC6 are assigned to JTAG pins and are not available as Macrocell outputs.
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