dmascc_cfg - Man Page

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.


--speed frequency

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.

--nrzi [0|1]

0 selects NRZ mode, 1 selects NRZI mode.

--clocks integer

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.

--txdelay milliseconds

Set transmit delay to milliseconds. Maximum is 2500 ms.

--txtime seconds

Set maximum time the transmitter may be active to seconds.

--sqdelay milliseconds

Set the squelch delay to milliseconds. Maximum delay is 2500 ms.

--slottime milliseconds

Set the slot time to milliseconds. Maximum slottime is 2500 ms.

--waittime milliseconds

Set the minimum time between the transmitter turning off to when it turns on to milliseconds. Maximum wait time is 2500 ms.

--persist f

Set the persistance parameter to f. Must be between 0 and 255  (inclusive).

--dma channel

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 Programmer's Manual