AN1949 STMicroelectronics, AN1949 Datasheet - Page 9

• Manufacturer Part Number: AN1949
• Description: RFID Reader using STMicroelectronics PSD MCU and CRX14 Coupler to Implement a China National ID Card Reader
• Manufacturer: STMicroelectronics

THE FIRMWARE
Figure 7. Block Diagram
For the purposes of this demonstration, only the Secondary Flash memory of the µPSD has been used.
In Application Programming (IAP) is possible if both main and secondary Flash memory of the µPSD are
used.
Figure 8. Memory Map and Address Space
Firmware running on the µPSD will mainly control the operation of the CRX14, and communicate with the
PC. Firmware will continuously control the CRX14 to send enquiry signals to the proximity field. If there is
a National ID card within the field, the µPSD will command the CRX14 to read the information from the
card, and to send the information back to the PC via the USB or RS232. When receiving a write command
from the PC, the µPSD will command the CRX14 to write the information to the National ID card.
7FFFh
Contactless Coupler
0000h
Control Functions
(CRX14_fncs.c,
SR176_fncs.c)
Flash Memory Space
Chip and Tag
(upsd_i2c.c)
I 2 C Driver
(Code Space)
SECONDARY
FLASH
32KB
UART Driver
FFh
7Fh
00h
(serial.c)
INT. RAM
Addressing
Addressing
Internal RAM Space
(256 Bytes)
Indirect
Indirect
Direct
or
(main.c)
Main
SFR
Addressing
upsd_usb.c,
usb_desc.c)
USB Driver
(usb_usr.c,
Direct
AN1949 - APPLICATION NOTE
1FFFh
2000h
External RAM Space
Other Drivers
(Data Space)
EXT. RAM
(timer.c)
(MOVX)
8KB
AI09747
AI09746
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