MarsBoard/JTAG

Connection
The marsboard P2 connector includes the UART 0 and JTAG signals as 3.3V TTL! .

You will need to make a JTAG adapter to suit your JTAG debugger.

Check your JTAG tool's cable details for alternate pinouts.

Notes:

 * Ensure Linux power-management is disabled to connect reliably.

echo userspace > /sys/bus/cpu/devices/cpu0/cpufreq/scaling_governor echo 1 > /sys/bus/cpu/devices/cpu0/online echo 1 > /sys/bus/cpu/devices/cpu1/online

Lauterbach Trace32
; MarsBoard A20 Trace32 Script ; 2013-08-01   RESet SYStem.CPU CortexA7MPCore SYStem.CONFIG CoreNumber 2. CORE.ASSIGN 1. 2.   SYStem.JTAGCLOCK 20MHz SYStem.CONFIG MEMORYACCESSPORT 0. SYStem.CONFIG DEBUGACCESSPORT 1. SYStem.CONFIG COREBASE             0x80110000 0x80112000 SYStem.CONFIG BMCBASE              0x80111000 0x80113000 SYStem.Option EnReset OFF ; Allwinner A20 Details MAP.BONCHIP 0xffff0000--0xffff7fff Break.Implementation Program Onchip SYStem.Up