Panel gauge clock

Panel Gauge Clock

Building and Installing

From ./Build dir make clean and make all are available.

On the XMC1300 boot kit dev board, you can use jflash lite to install the hex file.

Flash with jflash lite [JFlashLite] and seggerjlink ToDo: jlink commander to flash from command line

Hardware

Current

Assume 50 mA max current. Probably closer to 25 mA

MCU

XMC1302-0064 12 mA max current 2-6 mA in sleep mode

Gauges

500 mV full scale 100 ohm resistance? = 5 mA each, 10 mA total

Batt Backup

Assume 50 mA load Assume max Vin over voltage = 7 v

Zener Power = .05 * 3.15 V = 158 mW

Curr lim resistor Resistance: 7v - 3.15v / 50mA = 77 ohm, select 75R then max vin becomes 3.75 + 3.15 = 6.9 V Power: 3.75v * 50 mA = 188 mW

Pushbutton Debounce

Status LED

Pin P0.0

Backlight LED

one LED in each gauge Pin P0.5 -> BCCU0.OUT1

Power supply Monitor

p2.6 -> ORC4.AIN interrupt if OOR, but does it interrupt if comes back in range?

Pushbuttons

p2.0 Time++ p2.1 Time-- p2.2 PB_A - generic pushbutton

Temperature sensor

XMC1302 internal accuracy +/- 6-10 deg C

UART

USIC 0 CH 1

p0.6 -> ALT7 -> U0C1.DOUT0 -> TX p0.7 -> U0C1.DX0D -> RX

8-n-1-n 115200

USB Serial cable

• Red cable: +5V
• Black cable: GND
• Green cable: TXD
• White cable: RXD

BCCU

p0.8 -> ALT1 -> BCCU0.OUT4 -> Hours p0.9 -> ALT1 -> BCCU0.OUT5 -> Minutes

SWD0

p0.14 -> SWDCLK p0.15 -> SWDIO

HW NOTES

TODO:

• DONE, C7 Tantalum needs polarity on silkscreen

• DONE, Use smaller silk text, 0.8h, 0.15s minimum

• DONE, Do not use D, R, C, designators, do use U, ?

• Improve usb layout tuned length

• DONE, R3, R4 should be 3k3 for 600mv full scale.

• DONE, D6, D7 led too bright. Use 0.5ma, 4k3 for 5v0, 910R for 3v3.

• DONE, U1 +/- input pins reversed.

• DONE, test point style and smaller

• DONE, reduce pcb size

• increase voltage on caps to 2-3x, 3x for tant.

• ADA4891-2 ordered wrong package

General note

• pre-wired board to wire connectors
• lost one led
• silkscreen and mask black/wht inverted
• 5v0 supply: 5.056
• 3v3 supply: 3.305

Led back light Brass faceplate for HH, MM Battery backup AC freq timing? Pushbutton time setting Alarm?

Picture of case Bakelight switch?