PSD813F2-A-70J STMicroelectronics, PSD813F2-A-70J Datasheet - Page 56

• Manufacturer Part Number: PSD813F2-A-70J
• Manufacturer: STMicroelectronics

Specifications of PSD813F2-A-70J

• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Package Type: PLCC
• Mounting: Surface Mount
• Pin Count: 52
• Lead Free Status / RoHS Status: Compliant

PLDS
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Input macrocells (IMC)
The CPLD has 24 input macrocells (IMC), one for each pin on ports A, B, and C. The
architecture of the input macrocells (IMC) is shown in
are individually configurable, and can be used as a latch, register, or to pass incoming port
signals prior to driving them onto the PLD input bus. The outputs of the input macrocells
(IMC) can be read by the MCU through the internal data bus.
The enable for the latch and clock for the register are driven by a multiplexer whose inputs
are a product term from the CPLD AND Array or the MCU Address Strobe (ALE/AS). Each
product term output is used to latch or clock four input macrocells (IMC). port inputs 3-0 can
be controlled by one product term and 7-4 by another.
Configurations for the input macrocells (IMC) are specified by equations written in PSDabel
(see Application Note AN1171). outputs of the input macrocells (IMC) can be read by the
MCU via the IMC buffer (see
Input macrocells (IMC) can use Address Strobe (ALE/AS, PD0) to latch address bits higher
than A15. Any latched addresses are routed to the PLDs as inputs.
Input macrocells (IMC) are particularly useful with handshaking communication applications
where two processors pass data back and forth through a common mailbox.
shows a typical configuration where the Master MCU writes to the port A Data Out register.
This, in turn, can be read by the Slave MCU via the activation of the “Slave-Read” output
enable product term.
The Slave can also write to the port A input macrocells (IMC) and the Master can then read
the input macrocells (IMC) directly.
Note that the “Slave-Read” and “Slave-Wr” signals are product terms that are derived from
the Slave MCU inputs Read Strobe (RD, CNTL1), Write Strobe (WR, CNTL0), and
Slave_CS.
Section 16: I/O
Doc ID 7833 Rev 7
ports).
Figure
16. The input macrocells (IMC)
Figure 17
PSD8XXFX