| Here we try to document what we know about the EEPROM Structure. |
| |
| Even with a 93xx66 EEPROM, at maximum 256 Bytes are used |
| |
| All important things happen in the first |
| 0x14(FT232/245), 0x16(FT2232CD), 0x18(FT232/245R) or 0x1a (FT2232H/4432H) bytes |
| |
| Type | Use extra EEPROM space |
| FT2XXB | No |
| |
| Byte.BIT| TYPE_AM TYPE_BM TYPE_2232C TYPE_R TYPE_2232H TYPE_4232H |
| 00.0 | 0 0 channel_a_type 232R/245R channel_a_type 0 |
| 00.1 | 0 0 channel_a_type channel_a_type 0 |
| 00.2 | 0 0 channel_a_type high_current channel_a_type 0 |
| 00.3 | 0 0 channel_a_driver channel_a_driver channel_a_driver channel_a_driver |
| 00.4 | 0 0 high_current_a 0 0 0 |
| 00.5 | 0 0 0 0 0 0 |
| 00.6 | 0 0 0 0 0 0 |
| 00.7 | 0 0 0 0 SUSPEND_DBUS7 channel_c_driver |
| |
| On TYPE_R 00.0 is set for the FT245R and cleared for the FT232R |
| On TYPE_R 00.3 set mean D2XX, on other devices VCP |
| |
| 01.0 | 0 0 channel_b_type channel_b_type 0 |
| 01.1 | 0 0 channel_b_type channel_b_type 0 |
| 01.2 | 0 0 channel_b_type 0 channel_b_type 0 |
| 01.3 | 0 0 channel_b_driver 0 channel_b_driver channel_b_driver |
| 01.4 | 0 0 high_current_b 0 0 0 |
| 01.5 | 0 0 0 0 0 0 |
| 01.6 | 0 0 0 0 0 |
| 01.7 | 0 0 0 0 0 channel_d_driver |
| |
| Fixme: Missing 4232H validation |
| |
| 02 | Vendor ID (VID) LSB (all) |
| 03 | Vendor ID (VID) MSB (all) |
| 04 | Product ID (PID) LSB (all) |
| 05 | Product ID (PID) MSB (all) |
| 06 | Device release number LSB (not tested on TYPE_4232H) |
| 07 | Device release number MSB (not tested on TYPE_4232H) |
| | |
| 08.4 | Battery powered |
| 08.5 | Remote wakeup |
| 08.6 | Self powered: 1, bus powered: 0 |
| 08.7 | Always 1 |
| | |
| 09 | Max power (mA/2) |
| | |
| Byte.BIT| TYPE_AM TYPE_BM TYPE_2232C TYPE_R TYPE_2232H TYPE_4232H |
| 0a.0 | 0 IsoIn IsoIn part A 0 0 0 |
| 0a.1 | 0 IsoOut IsoOut part A 0 0 0 |
| 0a.2 | 0 suspend_pull_down suspend_pull_down suspend_pull_down suspend_pull_down |
| 0a.3 | 0 use_serial use_serial use_serial |
| 0a.4 | 0 change_usb_version change_usb_version |
| 0a.5 | 0 0 IsoIn part B 0 0 0 |
| 0a.6 | 0 0 IsoOut part B 0 0 0 |
| 0a.7 | 0 - reserved |
| |
| 0b | TYPE_R Bitmask Invert, 0 else |
| Byte.BIT| TYPE_4232H |
| 0b.4 | channel_a_rs485enable |
| 0b.5 | channel_b_rs485enable |
| 0b.6 | channel_c_rs485enable |
| 0b.7 | channel_d_rs485enable |
| |
| Byte | TYPE_AM TYPE_BM TYPE_2232C TYPE_R TYPE_2232H TYPE_4232H |
| 0c | 0 USB-VER-LSB USB-VER-LSB 0 ? ? |
| 0d | 0 USB-VER-MSB USB-VER-MSB 0 ? ? |
| (On several FT2232H different values were observed -> The value is unused |
| if change USB version is not set, so it might contain garbage) |
| |
| 0e | OFFSET Vendor |
| 0f | Len VENDOR |
| |
| 10 | Offset Product |
| 11 | Length Product |
| |
| 12 | Offset Serial |
| 13 | Length Serial |
| |
| Byte.BIT| TYPE_AM TYPE_BM TYPE_2232C TYPE_R TYPE_2232H TYPE_4232H |
| 14.3:0 | UA UA CHIP CBUS[0] AL A |
| 14.7:0 | UA UA CHIP CBUS[1] AH B |
| 15.3:0 | UA UA 0 CBUS[2] BL C |
| 15.7:0 | UA UA 0 CBUS[3] BH D |
| 16.3:0 | UA UA UA CBUS[4] 0 0 |
| 16.7:0 | UA UA UA 0 0 0 |
| |
| CHIP values: |
| 0x46: EEPROM is a 93xx46 |
| 0x56: EEPROM is a 93xx56 |
| 0x66: EEPROM is a 93xx66 |
| |
| 17 UA UA UA 0 0 0 |
| 18 UA UA UA VENDOR CHIP CHIP |
| 19 UA UA UA VENDOR 0 0 |
| |
| 1a UA (all) |
| |
| |
| Additional fields after the serial string: |
| 0x00, 0x00 - reserved for "legacy port name prefix" |
| 0x00, 0x00 - reserved for plug and play options |
| (Observed values with PnP == 0: |
| 0x02 0x03 0x01 0x00) |
| |
| Note: The additional fields after the serial number string |
| collide with the official FTDI formula from AN_121 regarding |
| the start of the user area: |
| "Start Address = the address following the last byte of SerialNumber string." |
