PrincessPi/Precision-Timekeeping-Fuckery
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

idk fam im just vibing

Browse Source
This commit is contained in:
Princess Pi
2026-03-28 06:26:29 -06:00
parent abf39eb70d
commit 83fd804ed5
1 changed files with 38 additions and 53 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Grandfatherclock.md
+37 -52
View File
@@ -11,19 +11,17 @@
6. Best GPS Antenna+Cable for it
7. PPS Settings
8. UART Speed settings
9. Any pulse out (32kHz/ maybe?)
2. [Pulsar Clock](Pulsar-Clock.md)
2. RPI5
1. pulse out/in (32kHz 31.25us period/10mhz 1ns period?)
3. [Pulsar Clock](Pulsar-Clock.md)
1. all daaat shit lmao
## Hardware
1. Raspberry Pi 5 16GB
1. [Raspberry Pi 5 16GB](https://www.adafruit.com/product/6125)
1. Raspberry OS Lite
2. Will need to carefully use real time priority, maybe even pinned to a core?
3. gpsd, etc?
4. reading pulses/etc
5. uart?
1. gpsd, etc?
2. Reading GPIO Pulses/etc
3. UART?
```bash
sudo taskset -cp 2 1234 # set task pid 1234 pin to core 2
```
@@ -33,61 +31,52 @@ sudo chrt -f -p 90 1234 # set pid 1234 to priority 90 (1-99  highest)
```
1. RTC 32khz pulses (31.25us period)
2. pulsar readings
2. Pulsar readings
3. RTC set/read over i2c
4. GPS Module PPS
5. NVME hat for NVME boot (? IF NOT INTERFERE WITH GPIO SHIT)
1. NVME SSD (? IF NOT INTERFERE WITH GPIO SHIT)
6. **Custom Hat**
1. [Adafruit DS3231 RTC Precision I2C Breakout Module](https://www.adafruit.com/product/3013#tutorials) x1
[CR1220](https://www.adafruit.com/products/380) x1 (Battery)
7. [Gen 10 Timekeeping Specific GPS Module - NEO-F10T](https://gnss.store/collections/neo-f10t-timing-gnss-modules)
1.  [Buy Varieties (Europe)](https://gnss.store/collections/neo-f10t-timing-gnss-modules)
1.  
1. Make sure battery TYPE and APPLICATION is figured out
2. May have to solder in holder or something
8. GPS Module
1\. [Gen 10 Timekeeping Specific GPS Module - NEO-F10T](https://gnss.store/collections/neo-f10t-timing-gnss-modules)
1. [Product Summary](https://content.u-blox.com/sites/default/files/documents/NEO-F10T_ProductSummary_UBX-22025534.pdf)
2. [Data Sheet](https://content.u-blox.com/sites/default/files/documents/NEO-F10T_DataSheet_UBX-22022576.pdf)
3. [Hardware Integration Guide](https://content.u-blox.com/sites/default/files/documents/NEO-F10T_IntegrationManual_UBX-22018271.pdf)
4. [Chip Product Page](https://www.u-blox.com/en/product/neo-f10t-module)
```
2. Make sure GPIO pins are FUCKING 2.54mm AND 3.3v OR 5v
1. use goldddd pinssss~
3. GPS cable
1. check connectors
2. check adaptors
3. check variety
1. speed/length
2. check length
4. GPS antenna
1. check protos
2. check bands
3. check features
4. check connectors
```
1. [Buy Varieties (Europe)](https://gnss.store/collections/neo-f10t-timing-gnss-modules)
1. Make sure **BATTERY** **TYPE** and **APPLICATION** is figured out
2. May have to solder in holder or something
1. use the good solder/pins/wire :3
3. Make fuckin sure af you have a good fuckin pinout
4. check if can be configed via uart using [u-center-2](https://www.u-blox.com/en/u-center-2)?
1. figure out a convenient UART (Tigard/FT422H) and plug
2. Make sure GPIO pins are FUCKING **2.54mm** AND **3.3v** OR **5v**
1. use good/gold/copper pinssss/wire/solder
9. [Gen 10 Timekeeping Specific GPS Module - NEO-F10T](https://gnss.store/collections/neo-f10t-timing-gnss-modules)
10. [Product Summary](https://content.u-blox.com/sites/default/files/documents/NEO-F10T_ProductSummary_UBX-22025534.pdf)
11. [Data Sheet](https://content.u-blox.com/sites/default/files/documents/NEO-F10T_DataSheet_UBX-22022576.pdf)
12. [Hardware Integration Guide](https://content.u-blox.com/sites/default/files/documents/NEO-F10T_IntegrationManual_UBX-22018271.pdf)
13. [Chip Product Page](https://www.u-blox.com/en/product/neo-f10t-module)
9. GPS cable
1. check connectors
2. check adaptors
3. check variety
1. speed/length
2. check length
10. GPS antenna
1. check protos
2. check bands
3. check features
4. check connectors
## RPI5 Wiring
- [GPIO Simple Pinout](https://vilros.com/pages/raspberry-pi-5-pinout)
- [GPIO Detailed Pinout](https://pinout.xyz/pinout/3v3_power)
### Wiring of Note
- CLK/PCM/GPIO18/PIN12:
- CLK in/out up to 10mHz (1ns period)
- ![9824306b308e6d2d21274a5bfe933c6b.png](../../_resources/9824306b308e6d2d21274a5bfe933c6b.png)
- ![9824306b308e6d2d21274a5bfe933c6b.png](../../_resources/9824306b308e6d2d21274a5bfe933c6b-1.png)
- only one i2c port?
- mostly all 3v3?
- PCM is kinda like DAC?
@@ -95,15 +84,11 @@ sudo chrt -f -p 90 1234 # set pid 1234 to priority 90 (1-99  highest)
- PWM?
- find sum DAC/ADC? sumtin?
- **May have to nix double RTC Module**
### Wiring
- UART (GPS Module, tinker with speed)
- I2C (RTC)
- CLK/PCM/GPIO READ? (RTC 32khz pulse - 31.25us period)
## Operation Flow
Both RTCs loaded time over I2C, both inputting 32kHz (31.25us period) signal via GPIO
RTC time, GPS time, system time, GPS PPS, 32kHz (31.25us period) signal, pulsar readings:
@@ -128,8 +113,8 @@ RTC time, GPS time, system time, GPS PPS, 32kHz (31.25us period) signal, pulsar
4. Repeatability check
5. Accuracy check
6. Precision check
## Maybe
1. Play with PPS (dial faster?)
2. Play with UART speed (dial faster?)
3. tinker with 10mhz clock out/test/tinker
4. tinker with 32khz clock in/test/tinker