Hi, I am new here..
I want to ask lot of suggestion from u all.
I want to design a digital instrumentation circuit that contains DSO, logic analyzer, and a spectrum analyzer. Is there anyone here that can help me from where to start. I am really focusing on designing one by one first. But can the PIC18F4550 support all the design?
best regards from me. Thank you..
The instruments you wish to design are not simple. we need to know how much experience do you have in electronics and microcontrollers to help you. Best of luck
you can use "Microchip USB framework", its ready made USB firmware projects (HID, CDC, Mass storage,...etc) implemented in C for various hardware platforms including PIC18F4550, the issue seems to me easy as i implemented it before.
but remember you will use only MPLAB and C18 in order to use them, check hardware settings for the PIC18F4550 in the datasheet, very important.
this is the link of the Microchip USB framework:
**broken link removed**
USB control is the simple part of your project. For the other, it depends on the specification. If you regard acquiring of kHz audio
signals as "DSO", it can be simple too. Several 10 MS/s, as achieved by typical USB oscilloscope black boxes, is already demanding.
It requires special hardware and a profound analog and digital electronics background. Speed ranges of today's DSO are simply
unavailable without designing your own chips.
Today, a DSO or LA user would expect a higher data throughput than provided by full speed USB interface.
by the above tools i mentioned you can make one cheap DSO with limited capability like the input frequency is 50 Khs, you can use external A/D chip with higher sampling rate, also you can use a firmware from the "Microchip USB framework" supports full speed then you can get 1 Mbyte/second data rate, want to immigrate to faster then pick up some products from TI interfacing solutions and components.
i am doing the same now, so far i hav achieved hid as well as cdc protocols simulation in proteous, currently i m working on hard ware side.
will further inform you about my progress....