hm2_pktuart_read
NAME
hm2_pktuart_read — read data from a Hostmot2 PktUART buffer
SYNTAX
int hm2_pktuart_read ( char *name, unsigned char data[], u8 *num_frames, u16 *max_frame_length, u16 frame_sizes[] )
DESCRIPTION
hm2_pktuart_read reads data from the PktUART name.
name is a unique string given to each PktUART instance during hostmot2 setup.
The names of the available channels are printed to standard output during
the driver loading process and take the form:
hm2_<board name>.<board index>.pktuart.<index>
For example
hm2_5i25.0.pktuart.0
This function reads a variable number of PktUART packets from the specified
channel.
It should be used inside a realtime HAL component registered with the
main hostmot2 driver using the function hm2_pktuart_setup in the setup
code.
(*num_frames) * (*max_frame_length) should be <= sizeof data, which one tries
to estimate or guess before calling the function.
If there are more bytes in the buffer than the size of data array is, then
RxArraySizeError is returned.
Note that the PktUART MaxFrameSize is 1024 bytes as hard-coded in hostmot2.vhd
RETURN VALUE
Returns the number of bytes read on success and negative error codes on failure.
On return num_frames which pointer is passed by value is set to the number of successfully
datagrams read.
Negative error codes are:
-1 - low level read/write error
-EINVAL - any PktUART configuration error per instance
-110 - RxStartbitError, Rx mode register error
-111 - RxOverrunError, Rx mode register error
-114 - RxRCFIFOError, Rx mode register error
-1115 - RxPacketOverrrunError, Rx count register error
-1114 - RxPacketStartbitError, Rx count register error
-1120 - RxPacketSizeZero, the size of the received packet is zero
-1140 - RxArraySizeError, the size of the data array is not large enough
LICENCE
Issued under the terms of the GPL v2 License or any later version
AUTHOR
Boris Skegin