BL4S200 User’s Manual
197
rn_read
int rn_read(int handle, int regno, char *recdata, int datalen);
FUNCTION DESCRIPTION
Reads a string from the specified device and register. Waits for results.
This function will
check device information to determine that the peripheral card is connected to a master.
PARAMETERS
handle
address index to device information. Use
rn_device()
or
rn_find()
to establish the handle.
regno
command register number as designated by each device.
recdata
pointer to the address of the string to read from the device.
datalen
number of bytes to read (0–15).
NOTE:
A data length of 0 will transmit the one-byte command register number.
RETURN VALUE
The status byte from the previous command. -1 means that device information indicates
the peripheral card is not connected to the master, and -2 means that the data length was
greater than 15.
SEE ALSO
rn_write