Is there a chip for 16-bit parallel to USB

[jitun2]

I am designing a project where i need to send 16(greater than equal to 16) bit of parallel data through the USB port. The chip FT245BM lets you send and receive 8-bit of data parallely. Does anybody knows about any other chip that is same as FT245BM but has a higher data bus width?

Is there a better adc that ADC0820. Better means higher sampling rate (lower conversion time)? It should be compatible to be interfaced with a microprocessor/microcontroller.

 

[Oznog]

There are a few PICs with USB functionality which also have 10-bit (some now have 12-bit) ADCs onboard.

 

[kchriste]

Why can't you just send it as two 8bit chunks?

 

[Sceadwian]

Considering USB is a serial bus you're only going to get one bit at a time no matter what chip you use! =) kchristie is right juat send two bytes at the same time, the data is sent in discrete packets much bigger (usually) than 8 bits at a time anyways. Usually you stuff the buffer as fast as you can and it sends a few hundred bytes at a time while the buffer is refilling. If you try to transmit individual bytes or words at a time the packet overhead becomes better than half of the data stream and your available bandwidth drops to less than you can do on a normal serial port pretty fast.

 

[Nigel Goodwin]

Considering USB is a serial bus you're only going to get one bit at a time no matter what chip you use! =) kchristie is right juat send two bytes at the same time, the data is sent in discrete packets much bigger (usually) than 8 bits at a time anyways. Usually you stuff the buffer as fast as you can and it sends a few hundred bytes at a time while the buffer is refilling. If you try to transmit individual bytes or words at a time the packet overhead becomes better than half of the data stream and your available bandwidth drops to less than you can do on a normal serial port pretty fast.

One byte at a time drops to about the same as a serial port at 9600 baud, due to the overhead associated with sending USB packets.

 

[Sceadwian]

Depends on the host/device protocol. But sounds about right. It's really horrible. USB can only ever 'shine' during bulk data transfers, with the largest possible packet size, even with low latency audio devices the bandwidth can get choked depending on the latency.

 

[jitun2]

I think I can send the 16 bit in two phases.