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Problem in receiving data to PIC MCU from Barcode Scanner thru' MAX3421E

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speedEC

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Dear all,
I am interfacing Barcode Scanner (USB) with PIC MCU thru' MAX3421E. I can able to connect and Enumerate the Scanner. But after that, I could not able to receive the barcode value from barcode scanner when reading. Barcode Scanner sounds good-read. It works well with PC (but we have to open a notepad or similar text editor to receive data).
I have enabled RWUIE (Remote Wake Up Interrupt) in MAX3421E and waiting for RWUIRQ interrupt to occur. When I read the barcode label and after barcode read it sends good-read, but RWUIRQ not interrupt occurred.
I have enabled RWUIE in HIEN register (R26) & IE in CPUCTL register (R16). I have tested the INT pin for other interrupts, for example Bus Reset, USB Disconnect, etc. All are working OK except, RWUIRQ.

I have SUSPENDED the Peripheral (Scanner) by seting the SOFKAENB = 0. So, after this I am waiting for either USB Disconnect or RWUIRQ occur. If I disconnect USB, interrupt correctly occur but only RWUIRQ DOES NOT.

USB Host Shield for Arduino used (for MAX3421E)., +3.3V
PIC MCU, +5V
BARCODE SCANNER(USB TYPE- BUS POWERED), +5V Given from adapter

LEVEL SHIFT USED between PIC and MAX3421E.

Any idea?
thank you.

- - - Updated - - -

Datasheet info added:
 

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Hi,

I don´t think the host needs to suspend the bus.
Or do you do this because of power saving.?

In either way. Try to focus on the communication.
If everything works you may do optimisations later.


Klaus
 

Even in un-suspended mode, RWUIRQ not set when Barcode scanner sends data.
 

I have contacted the MAXIM for this issue. They told me that they did not check the module for Barcode Scanner. So, asked me to analyze the flow in PIC24FJ.. (used to communicate with scanner thru' USB) and implement / modify the code according to. I read somewhere else on the web that MAX3421E requires at least 10ms signal duration for enabling interrupt. The barcode scanner signal is less that 10ms. So, we cannot use MAX3421E for accesssing Barcode Scanner. So, I have dropped the idea of using MAX3421E and preferred to use PIC24FJ...uC.

Thank you all.
bye
 

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