Function Com_LSR() Foundation
Reads the Line Status Register.
Syntax
Com_LSR( <nComPortNum> ;
) --> nLSRReturn
Com_LSR() returns the contents of the Line Status Register as a numeric value. The function IsBit() must be used to detect which bits are set.
Description
#define constants to be used for IsBit() are found in XBTCOM.CH
Bits set in Com_LSR() return value
| Bit | Constant | Description |
|---|---|---|
| No bit set | LSR_ERROR | something went wrong or LSR = 0 |
| Bit 1 set | LSR_DATA_READY | there is data in the transmit buffer |
| Bit 2 set | LSR_OVERRUN_ERR | buffer overflow or overflow in UART |
| Bit 3 set | LSR_PARITY_ERR | UART detected a parity error |
| Bit 4 set | LSR_FRAMING_ERR | UART detected a framing error |
| Bit 5 set | LSR_BREAK | set if BREAK has been detected |
| All other bits will be set to 0: | ||
| LSR_TRANS_HOLD_EMPTY | not supported | |
| LSR_TRANS_EMPTY | not supported |
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