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ECAN1000 User’s Manual 19 BDM-610020026 rev B
Chapter 5
B
OARD OPERATION AND PROGRAMMING
This chapter shows you how to program and use your ECAN1000HR. It
provides a complete description of the internal memory map of the chip
and a detailed discussion of the internal registers to aid you in program-
ming your CAN controller chip. The full functionality of the ECAN1000HR
is described in the attached datasheet reprint from Philips on the
SJA1000 CAN controller chip.
Defining the Memory Map
The memory map of the ECAN1000HR occupies 2 bytes of host PC I/O
memory space. This 3-byte window is freely selectable by the user as de-
scribed in
Chapter 2, Table 2. After setting the base address you have
access to the internal resources of the SJA1000 CAN controller chip.
These resources are described in the next sections reprinted from the
SJA1000 chip specific user’s manual.
ADDRESS Description
BASE+00h ADDRESS
BASE+01h DATA of ADDRESS
BASE+02h HARDWARE RESET
OF SJA1000
Table 5: ECAN Memory Map
The SJA1000 chip access is multiplexed in such a way that the host must
first write to BASE+0 the internal address of the CAN chip and after that
perform a write to address BASE+1 with the actual data to be written into
the desired memory location. An example is listed below using “C” syn-
tax. (We assume base address is 300H.)
Write 78H to the CAN controller Control byte located in the on-chip ad-
dress 0.
outp(0x300,0x00);
outp(0x301,0x78);
Address BASE+02h is a hardware-reset function of the SJA1000. Performing a read or
write to this address will cause a hardware reset to the CAN controller. You may need
to reset the chip in case of an unrecoverable error in the CAN controller chip.
On the following pages is attached the chip specific user’s manual
for the SJA1000 CAN controller chip.