From 0a8b5c55cf0769e475717d8b5f37d84f20914150 Mon Sep 17 00:00:00 2001 From: Bdale Garbee Date: Fri, 18 Sep 2020 22:55:29 -0600 Subject: [PATCH] create a ToDo file to document work needed on Altus Metrum products --- ToDo | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 ToDo diff --git a/ToDo b/ToDo new file mode 100644 index 0000000..3ba12cc --- /dev/null +++ b/ToDo @@ -0,0 +1,23 @@ +- rationalize LED current limiting resistors to use 1k everywhere except + TeleLaunch products using high-intensity, sunlight-readable LEDs that need + different values + +- switch all 32 MHz and 40 MHz crystals to a 2.0x1.6 mm packages, using a + footprint that has the outside dimentions of the ECX-1637B and inter-pad + spacings from the Murata XRCGB40M000F1S1LR0 to ensure we can change crystals + over time if needed. + + - switch all STM32 based products to 32 MHz crystals for the SOC except + TeleDongle, which could move to an STM32F042 and sync to USB with no + crystal. Absolute crystal specs aren't very important here, but it's + hard not to spend a fracton of a cent more for parts Bdale likes... + + best choice: DK 490-14308-2-ND + + - switch all CC1200 based products to 40 MHz crystal in 2.0x1.6 mm package, + with the possible exception of TeleMini/TeleMicro if that's just too hard. + We care about frequency accuracy and stability for these. + + cheapest credible: DK XC3069TR-ND + currently available: DK 490-XRCGB40M000F1S1LR0TR-ND + -- 2.47.2