BLAHAJ
/
libsigrok
10
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

asix-sigma: reword list of sample rates, (try to) use 1/2/5 steps 

The driver got extended in a previous commit to accept any hardware
supported samplerate in the setter API, although the list call does
suggest a discrete set of rates (a subset of the hardware capabilities).
Update a comment to catch up with the implementation.

Drop the 250kHz item, it's too close to 200kHz. Add a 2MHz item to
achieve a more consistent 1/2/5 sequence in each decade. Unfortunately
50MHz and an integer divider will never result in 20MHz, that's why
25MHz is an exception to this rule (has been before, just "stands out
more perceivably" in this adjusted sequence).
This commit is contained in:
Gerhard Sittig 2020-05-12 21:57:13 +02:00
parent c749d1ca57
commit b65649f6b9
1 changed files with 14 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
src/hardware/asix-sigma/protocol.c
View File

@ -27,22 +27,22 @@
#include "protocol.h"
/*
* The ASIX Sigma supports arbitrary integer frequency divider in
* the 50MHz mode. The divider is in range 1...256 , allowing for
* very precise sampling rate selection. This driver supports only
* a subset of the sampling rates.
* The ASIX SIGMA hardware supports fixed 200MHz and 100MHz sample rates
* (by means of separate firmware images). As well as 50MHz divided by
* an integer divider in the 1..256 range (by the "typical" firmware).
* Which translates to a strict lower boundary of around 195kHz.
*
* This driver "suggests" a subset of the available rates by listing a
* few discrete values, while setter routines accept any user specified
* rate that is supported by the hardware.
*/
SR_PRIV const uint64_t samplerates[] = {
SR_KHZ(200), /* div=250 */
SR_KHZ(250), /* div=200 */
SR_KHZ(500), /* div=100 */
SR_MHZ(1), /* div=50 */
SR_MHZ(5), /* div=10 */
SR_MHZ(10), /* div=5 */
SR_MHZ(25), /* div=2 */
SR_MHZ(50), /* div=1 */
SR_MHZ(100), /* Special FW needed */
SR_MHZ(200), /* Special FW needed */
/* 50MHz and integer divider. 1/2/5 steps (where possible). */
SR_KHZ(200), SR_KHZ(500),
SR_MHZ(1), SR_MHZ(2), SR_MHZ(5),
SR_MHZ(10), SR_MHZ(25), SR_MHZ(50),
/* 100MHz/200MHz, fixed rates in special firmware. */
SR_MHZ(100), SR_MHZ(200),
};
SR_PRIV const size_t samplerates_count = ARRAY_SIZE(samplerates);