Master writes SPD0R

Slave inbound interrupt requested

Visible in status register

Slave writes status register

Slave writes SPD0R

/SLAVEATTN (PB7)

Visible in status register

Master writes status register

Figure 13-3. Slave Port Handshaking and Interrupts

Figure 13-4shows a sample connection of two slave Rabbits to a master Rabbit. The mas- ter drives the slave reset line for both slaves and provides the main processor clock from its own clock. There is no requirement that the master and slave share a clock, but doing so makes it unnecessary to connect a crystal to the slaves. Each Rabbit in Figure 13-4has to have RAM memory. The master must also have flash memory. However, the slaves do not need nonvolatile memory since the master can cold boot them over the slave port and download their program. In order for this to happen, the SMODE0 and SMODE1 pins must be properly configured as shown in Figure 13-4to begin a cold boot process at the end of the slave reset.

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Jameco Electronics 2000, 3000 manual Slaveattn PB7