VDrive2 - ROM upgrade cable
Reprising lost post.
FTDI has confirmed VDrive2 fw v3.54 has a bug that prevents update from the USB device and requires updating via the vprog_com.exe program using a level shifting cable to ensure that only 3.3V is applied to the UART (Despite the UART being happy with 5V from the PICAXE in normal operation).
Have reviewed historical posts by Tarzan and Therowes (Archive #23).
@Tarzan
The Max232 datasheet indicates it will output at 7V so would not have thought use of this would be safe or are you implementing some additional techniques to reduce the voltage?
@Therowes
Have built a cable using a 74LS04 with
Tx PC -> 1/6 74LS04 -> Rx VDrive2 UART
and
Tx -> VDrive2 UART -> 1/6 74LS04 -> Rx PC
5V supplied to VDrive2 and 74LS04 and common 0V for all including download cable.
Unused 1/6ths of 74LS04 tied either low or high.
PC COM1 set at 115200,n,8,1
Jumpers on VDrive2 set for bootloader and serial uart.
CTS on VDrive2 UART tied low.
When attempting to download the VProg program simply reports an initialisation error.
Any further suggestions/advice gratefully received.
Thanks
Reprising lost post.
FTDI has confirmed VDrive2 fw v3.54 has a bug that prevents update from the USB device and requires updating via the vprog_com.exe program using a level shifting cable to ensure that only 3.3V is applied to the UART (Despite the UART being happy with 5V from the PICAXE in normal operation).
Have reviewed historical posts by Tarzan and Therowes (Archive #23).
@Tarzan
The Max232 datasheet indicates it will output at 7V so would not have thought use of this would be safe or are you implementing some additional techniques to reduce the voltage?
@Therowes
Have built a cable using a 74LS04 with
Tx PC -> 1/6 74LS04 -> Rx VDrive2 UART
and
Tx -> VDrive2 UART -> 1/6 74LS04 -> Rx PC
5V supplied to VDrive2 and 74LS04 and common 0V for all including download cable.
Unused 1/6ths of 74LS04 tied either low or high.
PC COM1 set at 115200,n,8,1
Jumpers on VDrive2 set for bootloader and serial uart.
CTS on VDrive2 UART tied low.
When attempting to download the VProg program simply reports an initialisation error.
Any further suggestions/advice gratefully received.
Thanks
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