diff --git a/doc/MANUAL.md b/doc/MANUAL.md index e1f9bed..c44c9bd 100644 --- a/doc/MANUAL.md +++ b/doc/MANUAL.md @@ -126,15 +126,19 @@ There is SHUTDOWN pin where FPGA can turn OFF the board. This pin is not correctly routed on PCB v1.7 and needs hardware upgrade to make it work. -When board is ready to accept SHUTDOWN signal, LED D11 -(found on back side of the board near J1 pin 22) should +When RTC has 3V battery and its registers for current time, +alarm time and alarm logic are configured to trigger +RTC ALARM in the future, the board is ready to accept +SHUTDOWN signal, which is indicated when LED D11 +(found on back side of the board near J1 pin 22) is be very dimly lit, visible in the dark. -While D11 is dimly lit, power down -board by setting SHUTDOWN signal to 1 -(or shortly and carefully connect 1k resistor between SHUTDOWN pin of R13 -and 3.3V). -When RTC ALARM is triggered, board should turn ON and D11 should be OFF -indicating board can't enter SHUTDOWN until RTC ALARM flag is cleared. + +While D11 is dimly lit, board can be powered down by setting SHUTDOWN +signal to 1 from FPGA logic or by shortly and carefully connecting 1k +resistor between SHUTDOWN pin of R13 and 3.3V. +When RTC ALARM is triggered, board should turn ON. When D11 is OFF, +it is indicating that board can't enter SHUTDOWN, probably RTC ALARM +flag has to be cleared or other RTC registers configured. On J2 connector there are 2 pins for 5V external power input and output. They are located on top right, near pin labeled 27