Cypress EX-USB FX3 - 11. FX3 Boot Image Format; 11.1 Firmware Image Storage Format

FX3 Programmers Manual, Doc. # 001-64707 Rev. *C 149
11. FX3 Boot Image Format
The FX3 bootloader is capable of booting various sources based on the PMODE pin setting. The bootloader
requires the firmware image to be created with the following format:
11.1 Firmware Image Storage Format
Binary Image
Header
Length
(16-bit)
Description
wSignature 1 Signature 2 bytes initialize with “CY” ASCII text
bImageCTL; ½
For I2C/SPI EEPROM boot:
Bit0 = 0: execution binary file; 1: data file type
Bit3:1 (I2C size. Not used when booting from SPI EEPROM)
7: 128KB (Micro chip)
6: 64KB (128K ATMEL)
5: 32KB
4: 16KB
3: 8KB
2: 4KB
Note
Options 1 and 0 are reserved for future usage. Unpredicted result will occurred when boot-
ing in these modes.
Bit5:4(I2C speed on I2C Boot):
00: 100KHz
01: 400KHz
10: 1MHz
11: 3.4MHz (reserved)
Bit5:4(SPI speed on SPI boot):
00: 10 MHz
01: 20 MHz
10: 30 MHz
11: 40MHz (reserved).
Note
On I2C boot, bootloader power-up default will be set at 100KHz and it will adjust the I2C
speed if needed. On SPI boot, bootloader power-up default is set to 10 MHz and it will
adjust the SPI speed if needed.
Bit7:6: Reserved should be set to zero
bImageType; ½
bImageType=0xB0: normal FW binary image with checksum
bImageType=0xB1: Reserved for security image type
bImageType=0xB2: Boot with new VID and PID