PSD4235G2V-10U STMICROELECTRONICS [STMicroelectronics], PSD4235G2V-10U Datasheet - Page 60

• Manufacturer Part Number: PSD4235G2V-10U
• Description: Flash In-System Programmable (ISP) Peripherals for 16-bit MCUs
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

PSD4256G6V
MCU I/O Mode
In the MCU I/O mode, the MCU uses the PSD
Ports to expand its own I/O ports. By setting up the
CSIOP space, the ports on the PSD are mapped
into the MCU address space. The addresses of
the ports are listed in Table 6, page 19.
A port pin can be put into MCU I/O mode by writing
a 0 to the corresponding bit in the Control Register
(for Ports E, F and G). The MCU I/O direction may
be changed by writing to the corresponding bit in
the Direction Register, or by the output enable
product term. See the section entitled “Port Oper-
ating Modes”, on page 58. When the pin is config-
ured as an output, the content of the Data Out
Register drives the pin. When configured as an in-
put, the MCU can read the port input through the
Data In buffer. See Figure 27, page 59.
Ports A, B and C do not have Control Registers,
and are in MCU I/O mode by default. They can be
used for PLD I/O if they are specified in PSDsoft.
PLD I/O Mode
The PLD I/O Mode uses a port as an input to the
CPLD’s Input Macrocells (IMC), and/or as an out-
put from the CPLD’s Output Macrocells (OMC).
The output can be tri-stated with a control signal.
This output enable control signal can be defined
Table 39. Port Operating Modes
Note: 1. Can be multiplexed with other I/O functions.
60/100
This is preliminary information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
MCU I/O
PLD I/O
McellA Outputs
McellB Outputs
Additional Ext. CS Outputs
PLD Inputs
Address Out
Address In
Data Port
Peripheral I/O
JTAG ISP
MCU RESET Mode
2. Available to Motorola 16-bit 683xx and HC16 families of MCUs.
Port Mode
2
Port A
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
Port B
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
Port C
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
by a product term from the PLD, or by resetting the
corresponding bit in the Direction Register to 0.
The corresponding bit in the Direction Register
must not be set to 1 if the pin is defined for a PLD
input signal in PSDsoft. The PLD I/O mode is
specified in PSDsoft by declaring the port pins,
and then specifying an equation in PSDsoft.
Address Out Mode
For MCUs with a multiplexed address/data bus,
Address Out mode can be used to drive latched
addresses onto the port pins. These port pins can,
in turn, drive external devices. Either the output
enable or the corresponding bits of both the Direc-
tion Register and Control Register must be set to
a 1 for pins to use Address Out mode. This must
be done by the MCU at run-time. See Table 41,
page 61 for the address output pin assignments on
Ports E, F and G for various MCUs.
Note: Do not drive address signals with Address
Out Mode to an external memory device if it is in-
tended for the MCU to Boot from the external de-
vice. The MCU must first Boot from PSD memory
so the Direction and Control register bits can be
set.
Port D
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
Yes (A7 –
Port E
Yes
Yes
No
No
No
No
No
No
No
No
0)
1
Yes (A7 –
Port F
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
0)
or (A15 – 8)
Yes (A7 –
Port G
Yes
Yes
Yes
No
No
No
No
No
No
No
0)