@cindex @code{l1_data} variable attribute
@cindex @code{l1_data_A} variable attribute
@cindex @code{l1_data_B} variable attribute
@cindex @code{l1_data} variable attribute
@cindex @code{l1_data_A} variable attribute
@cindex @code{l1_data_B} variable attribute
Variables with the @code{io} attribute are used to address
memory-mapped peripherals. If an address is specified, the variable
is assigned that address, else it is not assigned an address (it is
Variables with the @code{io} attribute are used to address
memory-mapped peripherals. If an address is specified, the variable
is assigned that address, else it is not assigned an address (it is
Variables with the @code{cb} attribute are used to access the control
bus, using special instructions. @code{addr} indicates the control bus
address. Example:
Variables with the @code{cb} attribute are used to access the control
bus, using special instructions. @code{addr} indicates the control bus
address. Example: