On (25 Nov 94) [EMAIL PROTECTED] wrote to All... > MAA26011 for <[email protected]>; Fri, 25 Nov 1994 12:21:03 +0100 > Date: Fri, 25 Nov 1994 12:12:16 +0100 > From: [EMAIL PROTECTED]
> On 24 Nov 94 22:14:49 +0000, Johnathan Taylor said: >> Have you got a centronics port on your sam? > No, it's a bog-standard Coupe. Shame, I hoped it'd have been one of those Sam-Elite things with built-in printer port... >> IF you have, a simple R2R >> potential divider network will give a reasonable 8bit DAC by simply >> outputing > > the 8bit sample data to the select LPT data I/O port:-) > But if I did that then no one else would be able to use it, would they? Not on the old unexpanded Sam but it would be usable on any Sam with a parallel port! I believe there's a Centronics port Dongle for the peecee that is one of these simple DACs:-) In theory it's possible to expand this idea to a proper interface that simultainously passes D0-D7 & A8-A15 to a 16bit latch and its output could feed a bigger R2R ladder to allow upto 16bit resolution! Data would be output by pre-loading B reg with the upper 8bits and A reg with lower 8bits and C with port location and executing out (c),a. Without too much time penalty too;-) Though I doubt we'd get full 16bit resolution due to digitally generated noise on the supply rails, but it'd certainly be better than an 8bit player! Regards Johnathan. ... Gravity doesn`t exist: the earth sucks. -- |Fidonet: Johnathan Taylor 2:2501/307.9 |Internet: [EMAIL PROTECTED] | | Standard disclaimer: The views of this user are strictly his own.
