achilikin/rdspi

Si4703 based RDS scanner for Raspberry Pi

rdspi's Issues

Problem with pulled-low RST pin on SparkFun Si4703 boards

This code is referenced in a nice tutorial on using the Si4703 with the RPi that I found:
https://tutorials-raspberrypi.com/use-raspberry-pi-as-a-radio-receiver-fm-car-radio-car-pc

However, that tutorial is built around the currently-available Si470x boards from Amazon, which appear to be based on the design from SparkFun. Unlike the PL102RT-S board targeted by this code, the SparkFun boards pull RST low (instead of high). This means that the strategy of setting GPIO23 as INPUT, used in the current code to take the device out of Reset mode, doesn't work - the pin stays low.

The tutorial author writes a small separate program which allows RdSpi to run once, but the more useful solution is to change RdSpi to affirmatively set GPIO23 as Output-High to pull the device out of RST.

I've implemented this change in my own fork: https://github.com/dpwe/RdSpi/tree/sparkfun-board

Although, on RPI4/Buster, I still have a problem that the reset only "works" every second invocation, so you have to run "./rdspi reset" twice to wake the device up. I think this is general decay of the SYSFS GPIO interface, but I'm not sure.

Identify the reception of a new RDS message in the presence of RDS bursts

I'm using this program within a system where I use single RDS messages (type 00A) as a control channel. It would be useful if there was a way of knowing where a new RDS message arrived. Therefore, I would like to know if it is safe to manually set the registers that I'm reading to something like -1, after retrieving its current value, and when a new RDS arrived, that register would change to a different value, letting me now that what I'm reading is from a different RDS message. Otherwise, the register would be set for too long. I need to receive a new RDS message each 80 ms or something like that.

Reading North America Call Signs

In North America, radio stations have 4-character call signs (e.g. "WNYC" or "KQED") which are encoded into the Program Identification (PI) code algorithmically (see section D.6 of the US RDBS standard, http://www.interactive-radio-system.com/docs/rbds1998.pdf). This replaces using the PS of GT0A to carry the station name.

I've adapted the "scan" and "spectrum" commands to obtain and the call letters from the PI instead of scanning for GT0A:
https://github.com/dpwe/RdSpi/tree/na_pi . However, I haven't preserved the GT0A.PS-reading code; we need some additional work to support both North American and European standards in the same code.

Raspberry 3

Hello achilikin,
I'm using the raspi 3 in combinition with the si470x chip.
I have already established the connection with the chip, as shown here:
root@raspberrypi:/home/pi/wiringPi/RdSpi# i2cdetect -y 1
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: — — — — — — — — — — — — —
10: 10 — — — — — — — — — — — — — — —
20: — — — — — — — — — — — — — — — —
30: — — — — — — — — — — — — — — — —
40: — — — — — — — — — — — — — — — —
50: — — — — — — — — — — — — — — — —
60: — — — — — — — — — — — — — — — —
70: — — — — — — — —

After that I want to reset the chip with the following command: root@raspberrypi:/home/pi/wiringPi/RdSpi# ./rdspi reset
Unable to read Si4703!
Communication error
And now I get Communication error. So have you an idea why is it so? Are your scripts combatable to Rasperry 3?
Thank you.

bug in scan mode

hello, i have a bug in scan mode or spectrum mode. Pi code is fixing to 0000 .
example :
9260 ---------------------------------- 34 ST
9330 ---------------------------------------- 40 ST 0000 'R CAMPUS'
9400 --------------- 15
9440 -------------------------------- 32 ST
9460 ----------------------------- 29
9500 ------------------------------------------ 42 ST 0000 ' RIRE '
9600 --------------------------- 27
9620 ---------------------------- 28
9660 --------------------------------------------------- 51 ST 0000 ' FUN '
9750 ----------------------------------------------- 47 ST 0000 ' MOUV '
9780 ----------------------------- 29
9880 ------------------------------- 31
10290 -------------------------------- 32 ST
10430 ----------------------------------------- 41 ST 0000 ' RTL '
10470 ---------------------------------------------- 46
10510 --------------------------------------------- 45
10640 ---------------------------------------------- 46 ST 0000 ' RFM '