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DMASCC_CFG(1) Linux Programmer's Manual DMASCC_CFG(1)


dmascc_cfg - Configure dmascc devices


dmascc <interface> [<options>]


dmascc_cfg is used to configure dmascc devices such as PI2 and PackeTwin cards. The --show option can be used by any user, all other options must be used by root.


Set frequency of baud rate generator to frequency. A value of 0 disables the baud rate generator and the digital PLL. Use the --show option to check whether the frequency you selected could be approximated with sufficient accuracy.
0 selects NRZ mode, 1 selects NRZI mode.
Set the clock mode. You may OR together three choices (other values are not supported and may cause strange results).

TX clock pin:

0x00 input
0x05 output TX clock *
0x06 output baud rate generator *
0x07 output digital PLL *

TX clock source:

0x00 RX clock pin
0x08 TX clock pin #
0x10 baud rate generator
0x18 digital PLL +

RX clock source:

0x00 RX clock pin
0x20 TX clock pin
0x40 baud rate generator
0x60 digital PLL +

* Not allowed on PI2 Port A if J3 is installed.

# TX clock pin must be configured as input.

+ Speed must be equal to 32 times the baud rate.

Set transmit delay to milliseconds. Maximum is 2500 ms.
Set maximum time the transmitter may be active to seconds.
Set the squelch delay to milliseconds. Maximum delay is 2500 ms.
Set the slot time to milliseconds. Maximum slottime is 2500 ms.
Set the minimum time between the transmitter turning off to when it turns on to milliseconds. Maximum wait time is 2500 ms.
Set the persistence parameter to f. Must be between 0 and 255 (inclusive).
Set the DMA channel to channel. Can be 1 or 3. Setting to 0 disables DMA.


dmascc_cfg does not check the parameters for validity. The driver or kernel may crash if you specify invalid values.


Klaus Kudielka

This manual page written by Craig Small <>
30 June 1999 Linux