2.4
Reset, powerup, and configuration
The MPS3 board provides five external resets to the FPGA.
Overview of reset system
The MPS3 board provides a hardware reset, and a software reset.
There are two hardware reset buttons. They perform the same function and both are labeled
PBRST
.
Pressing one of them puts the system into the standby state.
There are two On/Off soft reset buttons. Both are labeled
PBON
. Pressing one of them performs a
software reset, or if the board is already in the standby state, powers up the system.
The following figure shows the MPS3 board reset system, where the FPGA contains a user image.
FPGA
MPS3 FPGA Prototyping Board
SCC
MCC
User image
CB_nPOR CB_nRST FPGA_nRST
SCC
Debug
nTRST
CB_CFGnRST
Fixed PSUs
Fixed PSUs
EN
EN
JTAG
nSRST
Reset logic
GPIO
MCC reset
nRST
Hardware
reset push
buttons
On/Off Soft
reset push
buttons
PBRST
PBON
Figure 2-4 MPS3 board reset system
FPGA resets
FPGA_nRST
Board and FPGA reset including FPGA PLLs.
CB_nPOR
The main powerup reset for the FPGA image logic. If a
System Control Processor
(SCP) is
present in the design, releasing this reset might also trigger the powerup reset sequencing.
nTRST
Resets the CoreSight DAP.
CB_nRST, nSRST
CB_nRST
is the core reset. These inputs are ANDed together in the FPGA. They initiate
operation of the processors and enable the debug tools to debug the processors before they leave
reset.
2 Hardware description
2.4 Reset, powerup, and configuration
100765_0000_04_en
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