What is the memory map of free CE address space that can be safely used by user external peripherals (as addressed by the DataPort class)?

Created May 4, 2012

Tim Rohaly

The following was taken from a post by Chris Fox (Dallas Semiconductor) made on the TINI mailing list on 25 May 2000.

Here's a memory/address map:

Address (hex)     Chip Enable   Contents
	
000000 - 07FFFF	  *CE0          Flash ROM (on-board, 512K)
080000 - 0FFFFF	  *CE0          Image of Flash ROM (or off-board 512K Flash ROM on Socket board)
 
100000 - 17FFFF	  *CE1          Image of SRAM0 (512K)
180000 - 1FFFFF	  *CE1          SRAM0 (512K)

200000 - 27FFFF	  *CE2          SRAM1 (512K)
280000 - 2FFFFF	  *CE2          Image of SRAM1 (512K)

300000 - 307FFF	  *CE3          SMC Ethernet Controller
308000 - 30FFFF	  *CE3          Available Peripheral CODE & DATA Space (32K)
310000 - 31FFFF	  *CE3          Real Time Clock
320000 - 38FFFF	  *CE3          Available Peripheral CODE & DATA Space (896K)

000000 - 0FFFFF	  *PCE0         Off-board RAM or Peripheral space (1 meg)
100000 - 1FFFFF	  *PCE1         Off-board RAM or Peripheral space (1 meg)
200000 - 2FFFFF	  *PCE2         Off-board RAM or Peripheral space (1 meg)
300000 - 3FFFFF	  *PCE3         Off-board RAM or Peripheral space (1 meg)


Socket Board *CE3 Peripheral Decoding (Binary):

A23 <--------------------> A0
0011 10X0 XXXX XXXX 000X 0X10    Write strobes only, LCD Control Write
0011 10X0 XXXX XXXX 000X 1X10    Write strobes only, LCD Data Write

0011 10X0 XXXX XXXX 000X 0X00    Write strobes only, Parallel I/O lines ODB0-ODB7
0011 10X0 XXXX XXXX 000X 0X01    Write strobes only, Parallel I/O lines OCB0-OCB7

0011 10X0 XXXX XXXX 000X 0X00    Read strobes only, Parallel I/O lines IDB0-IDB7
0011 10X0 XXXX XXXX 000X 0X01    Read strobes only, Parallel I/O lines ICB0-ICB7

0011 10X0 XXXX XXXX 001X XXXX    P16552D Dual UART Access Read/Write

Under program control, each *CE segment can be either CODE & DATA space or just CODE ONLY space. When any *CEn segment is designated as CODE ONLY space, the corresponding *PCEn segment is enabled to be data. This means that code cannot be executed from any *PCE segment.

*NOTE: To allow the on-board Flash ROM to be supplanted for first-birthday initialization and other special applications, the *CE0 line is not connected to the Flash ROM on the TINI board. An external connection is required to connect *CE0 to *RCE0 (the Flash ROM) for proper operation of the TINI module.