Remote-processing RPC-330 Manuale Utente Scaricare il pdf (Pagina 20)

RAM MEMORY SECTION 5

Page 5-3 RPC-330

Figure 5-2 RPBASIC-52 memory map

The highest address in a 32K RAM system is 7FFFH.

Many times it is desirable to store an array containing a

"mixed" set of variables. Suppose you needed to save an

array m ade up of the following elements:

Bytes Type Description

1 Byte Job counter

2 Word Analog output offset

6 Floating Correction factor

20 String Job name

Total number of byes required for each array is 30 (add

1 for a < CR> at the end of the string).

The Job counter is incremented ever y time it is

completed. Analog output offset is an output constant or

other var iable used to initialize the outputs. Job name is

used with the display to identify a job.

For this example, suppose there are 20 of these arrays

that need to be set up. A program fragment is as

follows:

100 STRING 400,20 Initialize 20 string arrays

300 NO = 12 Element to fill

310 CF = 23.432 Correction factor

320 JC = JC + 1 Job counter

330 AC = 25 Analog offset

350 GOSUB 1000

500 NO = 5 Element to retrieve

510 GOSUB 2000 Retrieve variables

This subroutine stores variables CF, JC, A C, and string

$(1) into an array starting in segment 1, address 0.

1000 POKEB1, 30*NO, JC

1010 POKEW1,30*NO+ 1,AC

1020 POKEF1,30*NO+ 3,CF

1030 POKE$1, 30*NO+ 9,$(1)

1040 RETURN

Subroutine 2000 - 2040 retrieves data into variables CF,

JC and AC.

2000 JC = PEEKB(1,30*NO)

2010 AC = PEEKW (1,30*NO+ 1)

2020 CF = PEEKF (1,30*NO+ 3)

2030 $(1) = PEEK$(1, 30*NO+ 9)

2040 RETURN

You can store and retrieve strings and other kinds of

variables in this way. There are many variations of

PEEK and POKE statements. Refer to the RPBASIC-52

Software Supplement in this manual for additional

information and examples. A list of commands appears

at the end of this section.

BLOCK DATA TRANSFER

Blocks of data are transferred to and from RAM and

flash EPROM using BLOAD and BSAVE commands.

Block transfers are useful for loading and storing data,

look-up tables, text, etc. U p to 65,535 bytes can be

moved from RAM to EPROM or EPROM to RAM at

one time. The absolute number of bytes that can be

moved is limited by the RAM and EPR OM sizes.

Transfers from EPROM to RAM , using BLOAD, take

approximately 23.5 m s/1000 bytes. T ransfers from

RAM to EPROM , using BSAVE, are even longer at 100

ms/1000 bytes using a 512K byte EPROM. T his time is

even longer when smaller EPROM s are used (due to the

programming algorithm).

Serial port, tick timer, and external interrupts are

enabled dur ing these transfers. However, responses to

ONT ICK or ONIT R are delayed by the time it takes to

transfer data. W hen ONTIC K or ONITR must be

serviced faster, transfer data in sm aller blocks.

Refer to BLOAD and BSAVE in Appendix A for more

information.

1 2 ... 15 16 17 18 19 20 21 22 23 24 25 ... 47 48

Commenti su questo manuale

Nessun commento

Remote-processing RPC-330 Manuale Utente Pagina 20

Commenti su questo manuale

Prodotti e manuali riguardandi Computer Remote-processing RPC-330