Commodore RF512C - Page 41

35
100 IMPUT # 1,EN,EMS , ET,ES
110 PRINT EN , EMS,ET , ES
120 RETURN
This simple prog r am shows t he BLOC K -FREE and BLOC K- ALL OC ATE
func ti ons. If a block is bee n free, it can be a ll ocated without
er ror; otherwise, no block availab le erro r willi be appeared
And there has a rarely use B-E command. Be sure which buffer
w
il l t ake up the execu te block, be f ore you run your machine
prog r am.
DIRECT - MEMORY PROGRAMMING
By ana l ogy with PEEK , POKE and S YS in BASI C, it is easy to handle
B-R, B-W and B E in DO S.
10 INPUT " TYP E A WORD ";KS
20 L= LEN( KS)
30 CLOSE 1:0PEN 1,8, 15
40 PRINT# 1"M-W"CHRS(05)C HR S(05)C HR S(L)KS :CL OS E
45 OPEN 1,8,15
50 PRINT# 1, "M-R"CHRS(05) CHRS (05)C HR S(L)
60 FOR I=1 TO L:
70 GET# 1 ,KS
80 PRINT KS
90 NE XT I: PRIN F-DOES THIS CORRECT?"
100 C LO SE 1
110 OPEN 1, 8, 15
120 PRINT# 1, " M-E " C HR S (160)C HR S(234)
130 C
LOSE 1
In line 40, it use M-W as PO KE to pu t str i ng KS into drive's RAM .
Then, it use M-R as PEEK to get such string back . Finally, the
program use li ne 120 to execute a drive SYS - 5472