AT7913E
4.3.3
4.3.4
UART Serial Links
Two identical UARTs are provided for serial communications. The UARTs support data
frames with 8 data bits, one optional parity bit and one stop bit. To generate the bit-rate,
each UART has a programmable 12-bits clock divider. Hardware flow-control is sup-
ported through handshake signals.
16-bit General Purpose Input Output
The 16-bit general purpose input output port can be individually programmed as output
or input. Two registers are associated with the operation of the port; the combined
input/output register, and direction register. When read, the input/output register will
return the current value of the port; when written, the value will be driven on the port sig-
nals. The direction register defines the direction for each individual port.
4.3.5
Memory Interface
The SpaceWire-RTC memory interface is implemented using the LEON2-FT Memory
Controller that supports the following:
• 8-bit PROM with sequential EDAC,
• 8-bit SRAM with sequential EDAC
• 32-bit PROM/SRAM with parallel-EDAC
• 8, 16, 32 bit I/O without-EDAC (wait-state and/or ready handshake)
• 16 bit GPIO (byte-wise) when less than 32 bit memory used
4.4
On-Chip Memory
The SpaceWire-RTC device includes a fault tolerant on-chip SRAM with embedded
Error Detection And Correction (EDAC) and AMBA AHB slave interface.
One error is corrected and two errors are detected, which is done by using a (32, 7)
BCH code. Some of the features available are single error counter, diagnostic reads and
writes and auto-scrubbing (automatic correction of single errors during reads).
The on-chip memory comprises a 32-bit wide memory bank of 64 kbytes of data.
4.5
4.6
FIFO Interface
This FIFO memory can be accessed as an on-chip memory or as an external interface
of the chip via the Memory Interface.
The FIFO interface supports transmission and reception of blocks of data by use of cir-
cular buffers located in memory external to the core. Separate transmit and receive
buffers are assumed. Reception and transmission of data can be ongoing
simultaneously.
ADC/DAC Interface
The SpaceWire-RTC includes a combined analogue-to-digital converter (ADC) and digi-
tal-to-analogue converter (DAC) interface.
The ADC/DAC interface provides a combined signal interface to parallel ADC and DAC
devices. The two interfaces are merged both at the pin/pad level as well as at the inter-
face towards the AMBA bus. The interface supports simultaneously one ADC device
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ATMEL [ ATMEL ]
