AN1177 STMicroelectronics, AN1177 Datasheet - Page 15

• Manufacturer Part Number: AN1177
• Description: P51XA-PSD8XX DESIGN GUIDE
• Manufacturer: STMicroelectronics

AN1177 - APPLICATION NOTE
If this is the first use of the PSDpro, click on the “Htest” icon to perform a test of the PSDpro and the PC
port. After testing, place a PSD813F2 into the socket of the PSDpro and click on the “Program” icon. (The
.obj file is automatically loaded when this process is invoked). The messaging of PSDsoft Express will in-
form you when programming is complete.
This window is also helpful even if you do not have a PSDpro programmer. You can use this window to
see where the Merge MCU Firmware utility of PSDsoft Express has placed the P51XA firmware within
physical memory of the PSD. For example, you can click on the secondary Flash memory icon in the tool
bar. Notice the P51XA reset vector that would be at absolute MCU addresses 0000h and 0002h, translates
to PSD secondary Flash memory physical addresses 20000h and 20002h, respectively. To see how all of
your P51XA absolute addresses translated into physical PSD memory addresses, click Report->Address
Translation. The start and stop addresses in the report are the absolute MCU system addresses that you
have specified. The addresses shown in square brackets are direct physical addresses used by a device
programmer to access the memory elements of the PSD in a linear fashion (a special device programming
mode that the MCU cannot access).
ENHANCED DESIGN EXAMPLE
This second design example builds upon the first to add enhanced features to this ISP/IAP capable sys-
tem. The physical connections between the P51XA and PSD813F2 do not change, but the memory map
and chip select equations do. The focus of this enhanced design is to show how the memories of the
PSD813F2 can be used concurrently. This means swapping the boot code out of Program Space after the
initial boot sequence has completed. The boot code can then be updated if desired.
Required Changes in the PSDsoft Express Design Entry
The steps to implement the second design in PSDsoft Express are almost identical to those in the first
design. In fact, you can repeat the steps outlined in Sections 3.2.1 to 3.2.3, except you should give your
new project a different name.
Change the Page Register Definition. For section 3.2.4, you will need to define a logic bit that will allow
the swapping of memory segments within the PSD during IAP. To do so, with the “Page Register Defini-
tion” tab clicked in the “Design Assistant” screen, make the following addition: for pgr7, click the “logic”
checkbox and type “swap” in the “Name of Logic Signal” column. This bit will be used in the chip select
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