PSD813F2, PSD833F2, PSD834F2, PSD853F2, PSD854F2
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SUMMARY DESCRIPTION
The PSD8XXFX family of memory systems for mi-
crocontrollers (MCUs) brings In-System-Program-
mability (ISP) to Flash memory and programmable
logic. The result is a simple and flexible solution for
embedded designs. PSD devices combine many
of the peripheral functions found in MCU based
applications.
Table
1
summarizes all the devices in the
PSD834F2, PSD853F2, PSD854F2.
The CPLD in the PSD devices features an opti-
mized macrocell logic architecture. The PSD mac-
rocell was created to address the unique
requirements of embedded system designs. It al-
lows direct connection between the system ad-
dress/data bus, and the internal PSD registers, to
simplify communication between the MCU and
other supporting devices.
The PSD device includes a JTAG Serial Program-
ming interface, to allow In-System Programming
(ISP) of the
entire device
. This feature reduces de-
velopment time, simplifies the manufacturing flow,
and dramatically lowers the cost of field upgrades.
Using ST’s special Fast-JTAG programming, a de-
sign can be rapidly programmed into the PSD in as
little as seven seconds.
The innovative PSD8XXFX family solves key
problems faced by designers when managing dis-
crete Flash memory devices, such as:
–
First-time In-System Programming (ISP)
–
Complex address decoding
–
Simultaneous read and write to the device.
The JTAG Serial Interface block allows In-System
Programming (ISP), and eliminates the need for
an external Boot EPROM, or an external program-
mer. To simplify Flash memory updates, program
execution is performed from a secondary Flash
memory while the primary Flash memory is being
updated. This solution avoids the complicated
hardware and software overhead necessary to im-
plement IAP.
ST makes available a software development tool,
PSDsoft Express, that generates ANSI-C compli-
ant code for use with your target MCU. This code
allows you to manipulate the non-volatile memory
(NVM) within the PSD. Code examples are also
provided for:
–
Flash memory IAP via the UART of the host
MCU
–
Memory paging to execute code across
several PSD memory pages
–
Loading, reading, and manipulation of PSD
macrocells by the MCU.
Table 1. Product Range
Note: 1. All products support: JTAG serial ISP, MCU parallel ISP, ISP Flash memory, ISP CPLD, Security features, Power Management
Unit (PMU), Automatic Power-down (APD)
2. SRAM may be backed up using an external battery.
Part Number
(1)
Primary Flash
Memory
(8 Sectors)
Secondary
Flash Memory
4 Sectors)
SRAM
(2)
I/O Ports
Number of
Macrocells
Serial
ISP
JTAG/
ISC Port
Turbo
Mode
Input
Output
PSD813F2
1 Mbit
256 Kbit
16 Kbit
27
24
16
yes
yes
PSD813F3
1 Mbit
none
16 Kbit
27
24
16
yes
yes
PSD813F4
1 Mbit
256 Kbit
none
27
24
16
yes
yes
PSD813F5
1 Mbit
none
none
27
24
16
yes
yes
PSD833F2
1 Mbit
256 Kbit
64 Kbit
27
24
16
yes
yes
PSD834F2
2 Mbit
256 Kbit
64 Kbit
27
24
16
yes
yes
PSD853F2
1 Mbit
256 Kbit
256 Kbit
27
24
16
yes
yes
PSD854F2
2 Mbit
256 Kbit
256 Kbit
27
24
16
yes
yes