---
title: Hardware Constants
framework: serialdriverkit
role: collectionGroup
role_heading: API Collection
path: serialdriverkit/hardware-constants
---

# Hardware Constants

Configure your device with the appropriate parity and flow-control options.

## Topics

### Control Bits

- [PD_RS232_S_DTR](serialdriverkit/pd_rs232_s_dtr.md)
- [PD_RS232_S_DSR](serialdriverkit/pd_rs232_s_dsr.md)
- [PD_RS232_S_RTS](serialdriverkit/pd_rs232_s_rts.md)
- [PD_RS232_S_CTS](serialdriverkit/pd_rs232_s_cts.md)
- [PD_RS232_S_RXO](serialdriverkit/pd_rs232_s_rxo.md)
- [PD_RS232_S_TXO](serialdriverkit/pd_rs232_s_txo.md)
- [PD_RS232_S_DCD](serialdriverkit/pd_rs232_s_dcd.md)

### Parity Options

- [PD_RS232_PARITY_DEFAULT](serialdriverkit/pd_rs232_parity_default.md)
- [PD_RS232_PARITY_NONE](serialdriverkit/pd_rs232_parity_none.md)
- [PD_RS232_PARITY_ODD](serialdriverkit/pd_rs232_parity_odd.md)
- [PD_RS232_PARITY_EVEN](serialdriverkit/pd_rs232_parity_even.md)
- [PD_RS232_PARITY_MARK](serialdriverkit/pd_rs232_parity_mark.md)
- [PD_RS232_PARITY_SPACE](serialdriverkit/pd_rs232_parity_space.md)
- [PD_RS232_PARITY_ANY](serialdriverkit/pd_rs232_parity_any.md)

## See Also

### Programming the Modem

- [HwGetModemStatus](serialdriverkit/iouserserial/hwgetmodemstatus.md)
- [SetModemStatus](serialdriverkit/iouserserial/setmodemstatus.md)
- [HwResetFIFO](serialdriverkit/iouserserial/hwresetfifo.md)
- [HwSendBreak](serialdriverkit/iouserserial/hwsendbreak.md)
- [HwProgramBaudRate](serialdriverkit/iouserserial/hwprogrambaudrate.md)
- [HwProgramLatencyTimer](serialdriverkit/iouserserial/hwprogramlatencytimer.md)
- [HwProgramMCR](serialdriverkit/iouserserial/hwprogrammcr.md)
- [HwProgramUART](serialdriverkit/iouserserial/hwprogramuart.md)