RDC
®
RISC DSP Controller
R8810LV
RDC Semiconductor Co.
Rev:1.2
Subject to change without notice
31
Set 1: external ready is ignored.
Set 0: external ready is required.
Bit 1-0 : R1-R0
, Wait-State value. When R2 is set to 0, it can inserted wait-state into an access to the LCS memory area.
(R1,R0) = (0,0) -- 0 wait-state ; (R1,R0) = (0,1) -- 1 wait-state
(R1,R0) = (1,0) -- 2 wait-state ; (R1,R0) = (1,1) -- 3 wait-state
MCSx
The memory block of MCS4 - MCS0 can be located anywhere within the 1M bytes memory space, exclusive of the
areas associated with the UCS and LCS chip selects. The maximum MCSx active memory range is 512k bytes.
The MCS chip selects are programmed through two registers A6h and A8h, and these select pins are not active on reset. Both
A6h and A8h registers must be accessed with a read or write to activate MCS4 - MCS0 . There aren’t default value on A6h
and A8h registers, so the A6h and A8h must be programmed first before MCS4 - MCS0 active.
Bit 15-7 : BA19-BA13
, Base Address. The BA19-BA13 correspond to bits 19-13 of the 1M bytes (20-bits) programmable
base address of the MCS chip select block. The bits 12 to 0 of the base address are always 0.
The base address can be set to any integer multiple of the size of the memory block size selected in these bits. For
example, if the midrange block is 32Kbytes, only the bits BA19 to BA15 can be programmed. So the block address
could be locate at 20000h or 38000h but not in 22000h.
The base address of the MCS chip select can be set to 00000h only if the LCS chip select is not active. And the
MCS chip select address range is not allowed to overlap the LCS chip select address range.
The MCS chip select address range also is not allowed to overlap the UCS chip select address range.
Bit 8-3
: Reserved
Bit 2: R2
, Ready Mode. This bit is configured to enable/disable the wait states inserted for the MCS chip selects. The R1,R0
bits of this register determine the number of wait state to insert.
set to 1: external ready is ignored
set to 0: external ready is required
Bit 1-0 : R1-R0
, Wait-State value. The R1,R0 determines the number of wait states inserted into a MCS access.
(R1,R0) : (1,1) – 3 wait states , (1,0) – 2 wait states, (0,1) – 1 wait states , (0,0) – 0 wait states
Midranage Memory Chip Select Register
Offset : A6h
0
Reset Value :
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
BA19 - BA13
1
1
1
1
R2
R1
R0
1