AN1212 Freescale Semiconductor / Motorola, AN1212 Datasheet - Page 32
![no-image](/images/no-image-200.jpg)
AN1212
Manufacturer Part Number
AN1212
Description
J1850 Multiplex Bus Communication Using the MC68HC705C8 and the SC371016 J1850 Communications Interface (JCI)
Manufacturer
Freescale Semiconductor / Motorola
Datasheet
1.AN1212.pdf
(40 pages)
AN1212/D
01A9
01AB
01AE
01B0
01B2
01B4
01B6
01B8
01BA
01BC
01BF
01C1
01C3
01C5
01C7
01C9
01CB
01CD
01CF
01D1
01D3
01D5
01D6
01D7
01D8
32
3C70
CC0185
A601
B702
A603
B706
A65D
B70A
A6C0
C71FDF
3F42
1C42
A647
B743
A64F
B744
A657
B745
A65F
B746
1202
9D
9D
9D
9D
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
************************************************************************
*
*
*
************************************************************************
************************************************************************
*****
************************************************************************
*** Initialization of Port C for JCI Handshake ***
JCIRST:
*** Initialization of SPCR for JCI Serial Comm. ***
*** Option Reg. IRQ Sensitivity ***
*** Clear Txmit Control Register ***
*** Initialization of Receive Message Buffer Pointers ***
*** Release JCI Reset* Input ***
J1850 Multiplex Bus Communication Using the MC68HC705C8
and the SC371016 J1850 Communications Interface (JCI)
Freescale Semiconductor, Inc.
For More Information On This Product,
inc
jmp
lda
sta
lda
sta
lda
sta
lda
sta
clr
bset txi, txcntrl
lda
sta
lda
sta
lda
sta
lda
sta
bset rst,portc
nop
nop
nop
nop
vardata
doover
#%00000001
portc
#%00000011
ddrc
#$01011101
spcr
#%11000000
option
txcntrl
#buff1
msg1
#buff2
msg2
#buff3
msg3
#buff4
msg4
Go to: www.freescale.com
Initialization Subroutine
Subroutines
;Increment the variable data byte
;Jump back, and transmit again
;C7-C2 user i/o, C1 - reset*,
;C3-C0 - cs*
;C7-C2 - user assigned
;C1=C0 - outputs
;B7 - spie, B6 - spe, B4 - mstr
;B3 - cpol, B2 - cpha, B1:0 - Bit Rate
;Program RAM0=RAM1=0 for more RAM
;Program IRQ* for negative edge only
;This will prepare the transmit control
;register for Host/JCI communication
;Load location of message buffer w/id1
;in message buffer pointer msg1
;Load location of message buffer w/id2
;in message buffer pointer msg2
;Load location of message buffer w/id3
;in message buffer pointer msg3
;Load location of message buffer w/id4
;in message buffer pointer msg4
;Negate reset
;Delay to allow
;All internal registers in
;JCI to reset
MOTOROLA
*****
*
*
*