C515C datasheet(21/96 Pages) INFINEON

21 / 96 page

C515C

Data Sheet

2003-02

Control of XRAM/CAN Controller Access

The XRAM in the C515C is a memory area that is logically located at the upper end of

the external memory space, but is integrated on the chip. Because the XRAM and the

CAN controller is used in the same way as external data memory the same instruction

types (MOVX) must be used for accessing the XRAM. Two bits in SFR SYSCON,

XMAP0 and XMAP1, control the accesses to the XRAM and the CAN controller.

SYSCON

Special Function Register

(B1H)

C515C-8R Reset Value: X010XX01B

C515C-8E Reset Value: X010X001B

Bit XMAP0 is hardware protected. If it is reset once (XRAM/CAN controller access

enabled) it cannot be set by software. Only a reset operation will set the XMAP0 bit

again.

Bit

Function

XMAP1

XRAM/CAN controller visible access control

Control bit for RD/WR signals during XRAM/CAN Controller

accesses. If addresses are outside the XRAM/CAN controller

address range or if XRAM is disabled, this bit has no effect.

XMAP1 = 0: The signals RD and WR are not activated during

accesses to the XRAM/CAN Controller

XMAP1 = 1: Ports 0, 2 and the signals RD and WR are activated

during accesses to XRAM/CAN Controller. In this

mode, address and data information during

XRAM/CAN Controller accesses are visible externally.

XMAP0

Global XRAM/CAN controller access enable/disable control

XMAP0 = 0: The access to XRAM and CAN controller is enabled.

XMAP0 = 1: The access to XRAM and CAN controller is disabled

(default after reset). All MOVX accesses are

performed via the external bus. Further, this bit is

hardware protected.

76543210

Bit No.

MSB

LSB

EALE

RMAP

–

B1H

SYSCON

CSWO XMAP1

–PMOD

XMAP0

The function of the shaded bits is not described in this section.

C515C Datasheet(PDF) 21 Page - Infineon Technologies AG

C515C Datasheet(HTML) 21 Page - Infineon Technologies AG

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96

Datasheet Download

Link URL