RCA RMB-167 - Manual (Page 29)

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respectively. The code within the 604-byte download block pokes these bytes starting from
address 0. That is, these instructions are placed into memory, one word at a time, as data. The
following instructions are used.
mov R1, #0A55Ah ; begin: DISWDT
mov 0, R1
mov R1, #0A5A5h
mov 2, R1
mov R1, #0B54Ah ; EINIT
mov 4, R1
mov R1, #0B5B5h
mov 6, R1
This pattern is used throughout sections 2 and 3. First the word is written to register R1. Then
the register is copied to memory. The file BTL67.DAT contains the bytes downloaded to the
RMB-167 board during bootstrapping. The file BTL.SRC contains the source code.
The initialization routines configure the SYSCON register. The internal ROM is disabled and the
external bus is activated. Next the CSP and DPP registers are initialized. These steps need to
be completed before the EINIT instruction. Note that if the watchdog timer is to be disabled; this
too must be done before the EINIT instruction.