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GR716-DS-UM, May 2019, Version 1.29
296
www.cobham.com/gaisler
GR716
33
SpaceWire Interface and RMAP target
The GR716 microcontroller comprises a SpaceWire interface with RMAP support (GRSPW2) units.
The SpaceWire interface with RMAP controls its own external pins and has a unique AMBA address
described in chapter 2.11. The nominal SpaceWire interface is connected via LVDS transceivers to
external pins and the redundant interface is connected to external pins via the IOMUX.
The SpaceWire interface control and status registers are located on APB bus in the address range from
0x80100000 to 0x80100FFF. See GRSPW2 unit connections in the next drawing. The figure shows
memory locations and functions used for GRSPW2 configuration and control.
The primary clock gating unit
GRCLKGATE
described in section 26 is used to enable/disable the
SpaceWire interface. The unit
GRCLKGATE
can also be used to perform reset of the SpaceWire
interface Software must enable clock and release reset described in section 26 before configuration
and transmission can start.
External IO selection and configuration is made in the system IO and LVDS configuration registers
(
GRGPREG
) in the address range from 0x8000D000 to 0x8000D03F and 0x80007030. See section
7.1 for further information.
The system can be configured to protect and restrict access to the SpaceWire controller in the
MEM-
PROT
unit. See section 47 for more information.
33.1
Overview
The SpaceWire core provides an interface between the AHB bus and a SpaceWire network. It imple-
ments the SpaceWire standard (ECSS-E-ST-50-12C) with the protocol identification extension
(ECSS-E-ST-50-51C). The Remote Memory Access Protocol (RMAP) target implements the ECSS
standard (ECSS-E-ST-50-52C).
The SpaceWire interface is configured through a set of registers accessed through an APB interface.
Data is transferred through DMA channels using an AHB master interface.
Figure 47.
GR716 GRSPW2 bus and pin connection
GPIO0
LEON3FT
Processor
APB
(0x80000000-
0x800FFFFF)
IOMUX
GPIO63
Main AHB
(0x00000000-
0xFFFFFFFF)
Select Outputs
Enable GRSPW2 clocks
(0x8000D000 -
0x8000D03F)
(0x80006000 -
0x8000600F)
GRGPREG
Select LVDS
(0x80007030)
LVDSMUX
MEMPROT
Memory Protection
(0x8001A000 -
0x8001AFFF)
TX0
RX2
Bridge
GRCLKGATE
Bridge
APB
(0x80100000-
0x801FFFFF)
DMA
AHB
IMEM
128K
DMEM
64K
AM
BA
GRSPW2
Bri
dg
e