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DU(4) Kernel Interfaces Manual DU(4) NAME du, dp - DU-11 201 data-phone interface DESCRIPTION The dp0 file is a 201 data-phone interface. Read and write calls to dp0 are limited to a maximum of 512 bytes. Each write call is sent as a single record. Seven bits from each byte are written along with an eighth odd parity bit. The sync must be user supplied. Each read call returns characters received from a single record. Seven bits are re‐ turned unaltered; the eighth bit is set if the byte was not received in odd parity. A 10 second time out is set and a zero-byte record is re‐ turned if nothing is received in that time. FILES /dev/dp0 SEE ALSO dn(4) BUGS The name dp0 is a historical dreg. DU(4)