Spectrum Digital TMS320F240 Technical Reference page 14

Spectrum Digital, Inc
2.1.1 Power Connector
The F240 is powered by a 5 Volt only power supply which is available with the module.
The board requires 750 milliamps. The power is supplied via 2 millimeter jack J1. If
expansion boards are connected to the module a higher amperage power supply may
be necessary.
2.2 TMS320F240 Memory Interface
The EVM includes 64k Words of zero wait-state program ram memory and 64k words
of zero wait-state data ram memory, providing a total of 128 k words of off chip static
ram. The board also features 2 sockets for flash rom.
It is important to remember that internal memory has a higher precedence than the
external memory. For more information on the memory in the device populated in your
EVM card please refer to Texas Instruments TMS320F240 Users Guide. Futhermore,
it is important to take into account that external memory is affected by wait-states. Wait
state generation for off-chip memory space (data, program, or I/O) is done with the
Wait State Generation Register(WSGR). To obtain zero waitstate off-chip memory
bits in the WSGR must be appropriately programmed. The board powers up with 1
wait-state. The EVM board does not generate wait states via the ready signal for
external program and data memory accesses.
External memory decode is done via U19 a GAL20V8. The generic array device selects
the RAM, FLASH ROM, or on board peripherals. The equations for the GAL are
included in Appendix A. The figure below shows a zero wait state program space
memory read followed by a data space memory write.
2-4
TMS320F240 Evaluation Module Technical Reference